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Simple Summary: Understanding the genetics behind the reproductive traits of pigs is crucial for enhancing productivity and economic outcomes in the pork industry. In this study, we investigated the genetic factors influencing reproductive characteristics in Large White pigs. By analyzing the genetic data of 2237 sows from southern China, we identified specific genes and genetic markers associated with important reproductive traits, such as litter size. Our findings provide valuable insights that could help in developing targeted breeding strategies aimed at improving these traits. This research is not only significant for farmers and breeders but also contributes to a more sustainable and efficient approach to pig farming. (1) Background: Reproductive performance is crucial for the pork industry's success. The Large White pig is central to this, yet the genetic factors influencing its reproductive traits are not well understood, highlighting the need for further research. (2) Methods: This study utilized Genome-Wide Association Studies to explore the genetic basis of reproductive traits in the Large White pig. We collected data from 2237 Large White sows across four breeding herds in southern China, focusing on eight reproductive traits. Statistical analyses included principal component analysis, linkage disequilibrium analysis, and univariate linear mixed models to identify significant single-nucleotide polymorphisms and candidate genes. (3) Results: Forty-five significantly related SNPs and 17 potential candidate genes associated with litter traits were identified. Individuals with the TT genotype at SNP rs341909772 showed an increase of 1.24 in the number of piglets born alive (NBA) and 1.25 in the number of healthy births (NHBs) compared with those with the CC genotype. (4) Conclusions: The SNPs and genes identified in this study offer insights into the genetics of reproductive traits in the Large White pig, potentially guiding the development of breeding strategies to improve litter size. [ABSTRACT FROM AUTHOR]

Termites—one of the most abundant animal groups in tropical ecosystems—are vital in nutrient recycling, contributing significantly to maintaining ecosystem functioning. However, how selective they are in their litter food choice, and whether they prefer nutritious or less nutritious litter substrates, are still important unresolved questions.Here, we test the effect of litter traits on the removal of litter by fungus‐growing termites, a dominant group of macrodetritivores in the Serengeti‐Mara ecosystem. We used metal‐mesh litterbags to measure the mass loss of stem and leaf litter from 23 grass species after an incubation period of 61 days.Sheeting—soil deposits indicating termite presence—strongly increased with tannin and phenolic compounds, especially in leaf litter (R2 = 0.54), where highly aromatic species like Cymbopogon caesius and Bothriochloa insculpta exhibited the highest sheeting rates. Litterbags with sheeting displayed 66% higher mass loss on average compared to those without. Once termites had selected the substrate, mass loss increased consistently irrespective of litter traits.Quantifying the combined effects of sheeting frequency and differential mass loss, we found that fungus‐growing termites predominantly increased the mass loss of high‐nutrient litter. This was mainly due to additional mass loss in leaf litter, not stem litter, with tannin concentration being the primary predictor of enhanced overall decomposition by termites. This suggests termites ameliorate the otherwise adverse influence of plant secondary compounds on litter decomposition.Synthesis: Our results support the idea that fungus‐growing termites are generalists, as termites collected organic substrates with varying quality. The strong effect of phenolic compounds on sheeting rate implies that secondary compounds play an important role in termite substrate selection. The selective removal of substrates high in secondary compounds suggests fungus‐growing termites lift important constraints to microbial breakdown, potentially enhancing ecosystem‐level carbon and nutrient recycling rates. Termites play crucial roles in recycling organic matter across tropical biomes and our study highlights that the role of secondary compounds in their selection and detection in decomposition studies needs more attention [ABSTRACT FROM AUTHOR]

The biodiversity and activity of microorganisms are crucial for litter decomposition, but how litter traits at different stages of decomposition drive changes in microbial communities has yet to be thoroughly explored. In the typical alpine hilly area of the Qinghai–Tibet Plateau, three types of litter at different decomposition stages were selected under a natural Picea crassifolia (Picea crassifolia Kom.) forest: undecomposed (A-1), partially decomposed (A-2), and fully decomposed (A-3). By measuring physicochemical indicators, microbial diversity, and the composition of the litter at different decomposition stages, this study investigates the community changes and responses of bacteria to litter characteristic changes at different decomposition levels. The results show that with the increase in decomposition level, bacterial diversity increases, community structure changes, and network complexity gradually increases, while the changes in fungal communities are insignificant. Structural equation modeling indicates that the first principal component (PC1) of litter properties is significantly negatively correlated with bacterial diversity and positively correlated with bacterial community composition. There is no significant correlation between fungal diversity and community composition, indicating a closer relationship between bacteria and litter characteristics than fungi. In summary, with an increase in litter decomposition level, the diversity and network complexity of bacterial and fungal communities will significantly increase, which is related to the changes in various litter characteristics. This study provides a scientific basis for the regulatory mechanism of litter decomposition and turnover in the alpine hilly area of the Qinghai–Tibet Plateau, specifically in Picea crassifolia forests. [ABSTRACT FROM AUTHOR]

The negative effects of heat stress on swine reproduction have been well documented and the recent global warming trend caused by climate change is leading to more days with high temperatures every year. This has caused a reduction in litter trait performance of Landrace sows in Taiwan, a country extending across tropical and subtropical oceanic zones. Therefore, this study developed a modified model to determine which stages of pregnancy, before, early, middle, and late, had the largest impacts of heat stress on litter traits. A reaction norm model (RNM) was used to identify sows with high resilience to heat stress for litter traits followed by analysis of the modified model. Data from Landrace sows were collected from 2 farms in Taiwan between 2008 and 2021. A total of 11,059 records were collected for total number born (TNB), number born alive (NBA), and stillborn rate (STBR). The results showed that the heritabilities of TNB, NBA, and STBR were 0.170, 0.115, and 0.077, respectively. These results were similar between the conventional model and the modified model. In the modified model, the before and early stages of sow pregnancy were the significant periods for TNB and NBA (P  < 0.05), while the early and middle stages were significant for STBR (P  < 0.05). According to the RNM results, the heritability estimates for TNB, NBA, and STBR were 0.23 to 0.11, 0.18 to 0.08, and 0.10 to 0.04, respectively, showing a decrease from low temperature-humidity index (THI) to high THI. The minimum genetic correlations between the highest and the lowest THI for TNB, NBA, and STBR were 0.85, 0.64, and 0.80, respectively. The results of the RNM for breeding value showed re-ranking across THI values. In conclusion, similar results were obtained for heritability when the model was modified for heat stress estimation. Yet re-ranking of breeding values across THI could help farmers to select not only for improved litter trait performance but also for heat stress resilience of Landrace sows in Taiwan. [ABSTRACT FROM AUTHOR]

Records pertaining to 321 farrowings for calculation of farrowing interval and 214 farrowings related to litter traits, litter index, duration of farrowing and pre-weaning mortality were taken from 2nd farrowing to 4th farrowing of HD-K75, HD-K75 X Ghoongroo and Ghoongroo pigs maintained at private farms of Krishi Vigyan Kendra (KVK), Baksa operating villages were utilized to carry out a study on effect of farrowing interval on litter traits, litter index, duration of farrowing and pre-weaning mortality. Data were arbitrarily classified into 5 groups as per farrowing interval viz. Group A (up to 190 days), Group B(191 to 200 days), Group C(201 to 210 days), Group D(211 to 220 days) and Group E (above 221 days). The overall mean of litter size at birth (no.), litter weight at birth (Kg), litter size at weaning (no.), litter weight at weaning (Kg), litter index, duration of farrowing (hrs) and pre-weaning piglet mortality (%) was found to be 8.547±0.091, 9.446±0.107, 6.766±0.086, 66.468±0.789, 1.271±0.007, 3.601±0.052 and 20.404±0.794 respectively. The analysis of variance revealed that effect of farrowing interval had significant effect (P<0.05) on litter size at birth, litter weight at birth, litter size at weaning and litter weight at weaning. [ABSTRACT FROM AUTHOR]

The biodiversity of litter can regulate carbon and nutrient cycling during mixed decomposition. It is common knowledge that the decomposition rates of mixed litters frequently deviate from those predicted for these component litter species. However, the direction and magnitude of the nonadditive effects on the degradation of mixed litters remain difficult to predict. Previous studies have reported that the different carbon fractions of leaf litters responded to litter mixture differently, which may help to explain the ambiguous nonadditive effect of diversity on bulk litter decomposition. Therefore, we conducted decomposition experiments on 32 litter mixtures from seven common tree species to test the responses of different carbon fractions to litter diversity in subtropical forests. We found that the overall mass loss of the mixed litter was faster than that estimated from single species. The relative mixing effects (RMEs) of different carbon fractions exhibited different patterns to litter diversity and were driven by different aspects of litter functional dissimilarity. Soluble carbon fractions decomposed more slowly than expected from single species, while lignin fractions decayed more quickly. Moreover, we found that the RMEs of bulk litter decomposition may be determined by the lignin fraction decomposition. Our findings further support that distinguishing the response of different carbon fractions to litter diversity is important for elucidating the nonadditive effects of total litter decomposition. [ABSTRACT FROM AUTHOR]

Selection for reproductive components in various pig populations in the world has been successfully performed. This study aimed to estimate the genetic parameters and genetic trends of reproductive traits of Taiwan Duroc, Landrace, and Yorkshire pigs. Data were extracted from the Taiwan Swine Registry Database from 2009 to June 2018. The number of farrowing records used in this study was 6,504, 6,398, and 2,178 for Duroc, Landrace, and Yorkshire, respectively. Litter traits measured were the number of piglets born alive (NBA), number of piglets at 21 days of age (N21D), litter weight at birth (LWB), and litter weight at 21 days of age (LW21D). Variances estimates obtained from univariate analysis with a repeatability model were used to estimate heritability and repeatability. Heritability estimates were 0.058±0.017, 0.037±0.014, and 0.101±0.032 for NBA; 0.086±0.018, 0.102±0.019, and 0.151±0.035 for N21D; 0.036±0.011, 0.111±0.021, and 0.330±0.05 for LWB; 0.119±0.020, 0.168±0.023, and 0.237±0.045 for LW21D in the Duroc, Landrace, and Yorkshire breeds, respectively. The genetic trends of NBA were 0.005 piglets/year for the Duroc and 0.002/piglets for the Landrace. In Yorkshire, conversely, there was no significant genetic improvement of NBA, but there was a 0.011 kg/year improvement of LWB. Among all genetic trends, it was shown that genetic gain in Taiwan pig populations was very low. In addition, it also suggested that genomic selection could be used in the Taiwan pig breeding program to push the rate of genetic gain. [ABSTRACT FROM AUTHOR]

Cryptostegia madagascariensis is an invasive plant species that covers 11% of the Brazilian northeastern territory, but its role on the litter trait in tropical ecosystems remains unclear. Here, we analyzed and compared the litter deposition, litter nutrient content, soil organic matter, and the litter decay rate from invaded and non-invaded environments by C. madagascariensis at a tropical Cambisol. The PCA analysis revealed that litter deposition, litter quality, and soil organic matter were correlated with the invaded environment. We grew plant species in greenhouse conditions to obtain a standard litter material to use in our litter bags in field conditions. We found that litter decay rate was higher in the invaded environment than in the non-invaded one. Our results suggest that C. madagascariensis changes litter traits in tropical ecosystems that in turn create negative plant–soil feedback to the native species by creating a physical barrier on soil surface and to promote its own rhizosphere.

Although microbial communities play an important role in explaining plant litter decomposition rates, whether and how litter chemistry may alter catabolic capacities of soil microbial communities remains poorly studied.During a 1‐year litter decomposition experiment of 12 herbaceous species with contrasting litter chemistry, we examined the effect of plant litter type (roots vs. leaves) and litter chemical traits on the resulting capacity of soil microbial communities to degrade a wide range of carbon substrates of variable complexity (MicroResp™ method).Litter chemistry impacted both the total catabolic activity as well as specific catabolic capacities of microbial communities. In the early stages of litter decomposition total catabolic activity was mainly influenced by the amount of C and N in litter leachates, and litter N, P and Mg, then, later, by lignin concentrations. Some specific catabolic capacities could also be related to litter initial chemistry. Overall, litter trait effects on soil microbial communities decreased over time and the relative importance of traits shifted during the decomposition process.Our results highlight that litter chemistry is a strong driver of catabolic capacities of microbial decomposers and, while its effect fades with time, it remains substantial throughout the litter decomposition process. These long‐lasting effects of litter chemistry suggest a persistent control on microbial catabolic capacities in ecosystems with recurrent litter production. Soil microbial catabolic activities were driven by broadly the same chemical traits across leaf and root litters.Synthesis. Such long‐lasting effects of litter chemistry on catabolic capacities of microbial communities may represent a substantial indirect driver of the decomposition process. Disentangling the relative importance of this overlooked effect of litter chemistry on decomposition represents the next challenge. We argue that such research line should open ground‐breaking perspectives for reconsidering our current understanding of the mechanistic links between litter traits and decomposition rate. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Background and aim: Wherever sunlight reaches litter, there is potential for photodegradation to contribute to decomposition. Although recent studies have weighed the contribution of short wavelength visible and ultraviolet (UV) radiation as drivers of photodegradation, the relative importance of each spectral region across biomes and plant communities remains uncertain. Methods: We performed a systematic meta-analysis of studies that assessed photodegradation through spectrally selective attenuation of solar radiation, by synthesizing 30 published studies using field incubations of leaf litter from 110 plant species under ambient sunlight. Results: Globally, the full spectrum of sunlight significantly increased litter mass loss by 15.3% ± 1% across all studies compared to darkness. Blue light alone was responsible for most of this increase in mass loss (13.8% ± 1%), whereas neither UV radiation nor its individual constituents UV-B and UV-A radiation had significant effects at the global scale, being only important in specific environments. These waveband-dependent effects were modulated by climate and ecosystem type. Among initial litter traits, carbon content, lignin content, lignin to nitrogen ratio and SLA positively correlated with the rate of photodegradation. Global coverage of biomes and spectral regions was uneven across the meta-analysis potentially biasing the results, but also indicating where research in lacking. Conclusions: Across studies attenuating spectral regions of sunlight, our meta-analysis confirms that photodegradation is a significant driver of decomposition, but this effect is highly dependent on the spectral region considered. Blue light was the predominant driver of photodegradation across biomes rather than UV radiation. [ABSTRACT FROM AUTHOR]

The litter size and litter weight are the most important indicators of growth production system in goats as they are directly related to the survival and growth of the kids. The present attempt was made to estimate genetic parameters of litter traits such as litter size at birth (LSB), litter size at weaning (LSW), litter weight at birth (LWB) and litter weight at weaning (LWW) of Jakhrana breed of Indian goat. These traits were subjected to study variation due to direct additive genetic effects by adjusting non-genetic factors under linear mixed model. The data of litter records of 101 Jakhrana goats including pedigree information were processed and the results showed that the least-square means for LSB, LSW, LWB and LWW were 1.20 ± 0.05, 1.19 ± 0.05, 3.08 ± 0.11 and 12.11 ± 0.49, respectively. The direct heritability estimates for LSB, LSW, LWB and LWW were 0.17, 0.01, 0.001 and 0.10, respectively. The genetic (0.70–0.97) and phenotypic (0.61–0.92) correlation estimates among litter traits were high and positive. This study indicated that the additive variation among the early reproductive traits was low in range which does not provide a warrant for the improvement through selection. However, the evaluation of these traits has provided the current state of litter performance of Jakhrana goat which may be upgraded by managerial practices specially care and feeding of pregnant goats.

Cryptostegia madagascariensis is an invasive plant species that covers 11% of the Brazilian northeastern territory, but its role on the litter trait in tropical ecosystems remains unclear. Here, we analyzed and compared the litter deposition, litter nutrient content, soil organic matter, and the litter decay rate from invaded and non-invaded environments by C. madagascariensis at a tropical Cambisol. The PCA analysis revealed that litter deposition, litter quality, and soil organic matter were correlated with the invaded environment. We grew plant species in greenhouse conditions to obtain a standard litter material to use in our litter bags in field conditions. We found that litter decay rate was higher in the invaded environment than in the non-invaded one. Our results suggest that C. madagascariensis changes litter traits in tropical ecosystems that in turn create negative plant–soil feedback to the native species by creating a physical barrier on soil surface and to promote its own rhizosphere. [ABSTRACT FROM AUTHOR]

The repeatability multi-trait animal model procedure (MTDFREML) was used to analyze 93 litters born to 36 does with pedigrees from 9 sires and 13 dams. Litter weight traits (LW), which included (litter weight at birth, LWB; litter weight at 21 days, LW21; litter weight at weaning, LWW) and litter weight gain (LWG) were (litter weight gain from birth to 21 days, LWGB 21; litter weight gain from birth to weaning, LWGB W; litter weight gain from 21 days to weaning LWG21 W)on New-Zealand White (NZW) rabbits does for two consecutive years. Heritability estimates (ha²) of LW were low to moderate ranging from 0.13 to 0.18. While h 2 a for LWG traits ranged from 0.09 to 0.15. Estimates of genetic correlations were highly significant (P<0.01), moderate and high ranging from (0.754 to 0.975). As for rank correlation estimates obtained among breeding values were positive, moderate, and highly significant (P<0.01), ranging from (0.754 to 0.975). The ranges of the NZW does breeding values were 0.36, 0.63 and 0.81 kg for LWB, LW21 and LWW traits, were 86.0, 62.0 and 63.0 gm for LWGB 21; LWGB W and LWG21 W traits, respectively. In addition, the percentages of positive breeding values estimated ranged from 48.7 to 69.2% for LW and from 29.0 to 73.1% for LWG traits. The epigenetic trend of litter traits (LWW and LWG) for NZW does properties influenced by the environmental conditions, genetic variations were observed in the arrangement of the parity and year-season effects. Additionally, mentioned that it is possible to achieve slow, but simultaneous improvement of litter traits with a selection program. Conclusively, the current study showed that the selection for does of rabbits based on the highest 25% of breeding values will achieve a good selection plan in the future. [ABSTRACT FROM AUTHOR]

Summary: The objective of the current study was to estimate the genetic parameters for ewe productivity traits of Harnali sheep by examining non-genetic effects. The data records of 440 animals born to 85 sires and 259 dams were collected with respect to various traits such as litter size at birth (LSB), litter weight at birth (LWB), litter size at weaning (LSW), litter weight at weaning (LWW) and age at first lambing (AFL) for the period of 2001 to 2020. Genetic parameters were estimated by fitting a series of animal models using an average information restricted maximum likelihood (REML) algorithm in WOMBAT software. Least-squares analysis revealed significant (P < 0.05) influences of period of lambing, age and weight of ewe at lambing on the studied traits. These results indicated that heavier ewes had significantly higher (P < 0.05) values of litter weight traits than their counterparts. On the basis of likelihood ratio test, the estimates of direct heritability under best model for AFL, LSB, LWB, LSW and LWW were 0.06, 0.18, 0.09, 0.07 and 0.16, respectively. Maternal permanent environment effect made a significant contribution to the LSB trait (0.20). The genetic correlation between litter size and LWW was negative, while the remaining correlations were positive. The present results suggest that selection based on ewe productivity traits will result in low genetic progress and therefore the management role is more important for better gains. [ABSTRACT FROM AUTHOR]

Abstract Biodiversity is a major driver of numerous ecosystem functions. However, consequences of changes in forest biodiversity remain difficult to predict because of limited knowledge about how tree diversity influences ecosystem functions. Litter decomposition is a key process affecting nutrient cycling, productivity, and carbon storage and can be influenced by plant biodiversity. Leaf litter species composition, environmental conditions, and the detritivore community are main components of the decomposition process, but their complex interactions are poorly understood. In this study, we tested the effect of tree functional diversity (FD) on litter decomposition in a field experiment manipulating tree diversity and partitioned the effects of litter physiochemical diversity and the detritivore community. We used litterbags with different mesh sizes to separate the effects of microorganisms and microfauna, mesofauna, and macrofauna and monitored soil fauna using pitfall traps and earthworm extractions. We hypothesized that higher tree litter FD accelerates litter decomposition due to the availability of complementary food components and higher activity of detritivores. Although we did not find direct effects of tree FD on litter decomposition, we identified key litter traits and macrodetritivores that explained part of the process. Litter mass loss was found to decrease with an increase in leaf litter carbon:nitrogen ratio. Moreover, litter mass loss increased with an increasing density of epigeic earthworms, with most pronounced effects in litterbags with a smaller mesh size, indicating indirect effects. Higher litter FD and litter nutrient content were found to increase the density of surface‐dwelling macrofauna and epigeic earthworm biomass. Based on structural equation modeling, we conclude that tree FD has a weak positive effect on soil surface litter decomposition by increasing the density of epigeic earthworms and that litter nitrogen‐related traits play a central role in tree composition effects on soil fauna and decomposition.

Biodiversity loss, exotic plant invasion and climatic change are three important global changes that can affect litter decomposition. These effects may be interactive and these global changes thus need to be considered simultaneously. Here, we assembled herbaceous plant communities with five species richness levels (1, 2, 4, 8 or 16) and subjected them to a drought treatment (no, moderate or intensive drought) that was factorially combined with an invasion treatment (presence or absence of the non-native Symphyotrichum subulatum). We collected litter of these plant communities and let it decompose for 9 months in the plant communities from which it originated. Drought decreased litter decomposition, while invasion by S. subulatum had little impact. Increasing species richness decreased litter decomposition except under intensive drought. A structural equation model showed that drought and species richness affected litter decomposition indirectly through changes in litter nitrogen concentration rather than by altering quantity and diversity of soil meso-fauna or soil physico-chemical properties. The slowed litter decomposition under high species diversity originated from a sampling effect, specifically from low litter nitrogen concentrations in the two dominant species. We conclude that effects on litter decomposition rates that are mediated by changing concentrations of the limiting nutrient in litter need to be considered when predicting effects of global changes such as plant diversity loss. [ABSTRACT FROM AUTHOR]

Data on 96 progeny obtained from a random bred population of American Chinchilla, New Zealand White and Dutch breeds of rabbits were used to estimate heritability for body weight traits at day 14 through to week 14. The variance of components of heritability was estimated employing AIREMLF90 of BLUPF90 programme based on restricted maximum likelihood software and R-Software was used to calculate standard error of heritability. Heritability estimates for body weight were high and of similar range with values of 0.59±0.25, 0.73±0.21, 0.67±0.17, 0.53±0.29, 0.55±0.26, 0.64±0.20, 0.60±0.24 for 2, 4, 6, 8, 10, 12 and 14 weeks respectively. Heritability estimates for body weight recorded in this study imply that additive genetic effect was of importance at different stages of growth. Therefore, genetic improvement can be done through pedigree or individual selection. The results also indicate that rabbit breeders can predict breeding value from the heritability values estimated. [ABSTRACT FROM AUTHOR]

With continuous improvement of sow litter size, breeders are gradually paying more attention to the quality of litter traits that directly impact the production efficiency of pig companies, such as the rate of piglets born alive (RBA) and the rate of healthy births (RHB). The objectives of this study are to dissect the genetic basis of litter traits in pig and to identify valuable genes and genetic markers, especially pleiotropic, for pig breeding. Herein, 1140 Duroc pigs and 2046 reproduction records, 5 litter traits, including the number of healthy births (NHB), number of deformed fetuses (NDF), number of stillborn (NSB), RBA, and RHB, were used in this study. Subsequently, a genome-wide association study (GWAS) was performed for the five litter traits in the first two parities from two Duroc populations. A total of 76 significantly related SNPs and 10 potential candidate genes (CAV1 , DAB2 , FGF12 , FHOD3 , DYNC2H1 , GRHL1 , TCTN3 , PYROXD2 , MMP8 , MMP13, and PGR) were detected, including 13 pleiotropic SNPs that affected more than one litter trait. Finally, the functional enrichment analysis of functional genes that were closest to these significant SNPs indicated that most of the significant pathways were associated with hormone secretion and embryo and organ development. This study advances our understanding of the genetic mechanisms of litter traits, especially the survival rate of piglets born, and provides an opportunity to increase the quality of litter using marker-assisted selection or genomic selection in pigs. This study explored underlying genetic architecture of the survival rate of piglets born in two Duroc pig populations. A total of 13 pleiotropic SNPs that affected more than one litter trait. CAV1, DAB2, FGF12, FHOD3, DYNC2H1, GRHL1, TCTN3, PYROXD2, MMP8, MMP13, and PGR were found to be related to litter traits. [ABSTRACT FROM AUTHOR]

Aims: Soil processes in arid ecosystems are strongly controlled by resource scarcity. Grazing intensification can induce changes in ecosystem processes through multiple pathways, adding new constraints to those of local conditions. We focus on grazing-induced changes in litter traits and soil environment that may affect litter decomposition and N dynamics in temperate grass-shrub steppes. Methods: We performed three litterbag decomposition experiments to evaluate: i) the effect of litter traits in a common garden (ex situ), ii) the effect of soil environment using a foreign common litter substrate (in situ), and iii) the interactive effects of litter traits and soil environment (grazed vs. exclosure communities, reciprocal transplants in situ). Field experiments were replicated in three blocks with paired plots under a long-term exclosure (> 25 years) and under year-round sheep grazing. Local litter included mixtures of species of grasses and shrubs, separately. Results: Grazing exclusion did not alter litter decomposition rates, either through changes in litter traits or in soil environment. Nevertheless, N released during grass litter decomposition was 286% higher in exclosures than in grazing communities. The difference was associated to changes in litter C:N ratio. The effects were maintained when results were integrated to the entire litter community. Conclusion: Our study suggests that litter decomposition rates in arid steppes are strongly controlled by local drivers. Ungulate grazing does not have an important influence on litter mass loss, but it can exert a strong control on N flux during decomposition, by changing grass litter traits. [ABSTRACT FROM AUTHOR]

Summary: Improving litter size at birth (TNB) and the number of piglets born alive (NBA) are the main breeding goals related to litter traits, which are economically important. A better understanding of genetic architecture underlying TNB and NBA traits could increase pig production efficiency. However, most previous studies on these traits focus on additive genetic effects, while epistatic interactions underlying TNB and NBA traits has not yet been well investigated, which are essential to understand how traits‐related genes interact. Herein, we conducted genome scans of epistatic interactions underlying TNB and NBA traits in a total of 150 Chinese indigenous pigs (75 Jinhua and 75 Shengxian Spotted pigs) with high throughput genomic data. Based on SNPs with high interaction values and connectivity scores, we identified eight promising candidate genes (AKT2, TSC1, MTOR, PIK3R5, TIAM1, FGF14, RALB and ROR2) potentially associated with litter traits in pigs. Moreover, the underlying pathways, e.g., calcium ion transport, pointed out their roles in litter size‐related traits. Our findings provide new insight into genetic architecture of litter traits in pigs and will benefit economic profits in pig production. [ABSTRACT FROM AUTHOR]

Global variation in litter decomposition rates is driven by climate, decomposer taxa and litter quality. Most large‐scale studies of litter quality have made comparisons across species, rather than within a species sourced from different latitudes. Here, we aim to explore latitudinal variation in leaf litter decomposition rate and litter quality within a species.We investigated whether the typical interspecific pattern of increased litter lability at higher latitudes also holds within plant species, by comparing leaf litter decomposition rates and litter traits from stands of native Phragmites australis and exotic Spartina alterniflora in Chinese coastal wetlands spanning 20° of latitude using parallel greenhouse and field transplant experiments.We found that leaf litter from high‐latitude plants decomposed 46.6 ± 5.1% faster than that from low‐latitude conspecifics, with similar patterns in both plant species in both decomposition experiments. Higher lability of leaves from high latitudes was associated with lower levels of plant defensive compounds (phenolics and tannins) and higher levels of nutrients (Ca, Mg and Na). Litter from the exotic S. alterniflora decomposed faster than litter from the native P. australis, being consistent with lower defences and higher nutrient concentrations in S. alterniflora litter.Our results show that individual species follow the same pattern of increasing litter lability at higher latitudes previously reported in cross‐species geographical comparisons. Moreover, this pattern can develop rapidly (<4 decades) in an introduced species, raising the question of whether it is caused by phenotypic plasticity or adaptation. A free Plain Language Summary can be found within the Supporting Information of this article. [ABSTRACT FROM AUTHOR]

Key message: Local climate exerted a stronger effect on leaf litter decomposition of deciduousQuercus acutissimaCarruth. and evergreenQuercus glaucaThunb. than initial leaf litter quality: the decomposition was much faster for leaves of the two species in warm-temperate forest than in the cool-temperate one. Context: Litter decomposition mainly depends on initial litter quality (e.g., physical features and nutrient content). However, the effects of litter quality on decomposition remain inconclusive in different climatic zones due to complex interaction with climatic factors. Aims: This study investigated the effect of litter quality and climatic factors on litter decomposition of deciduous Quercus acutissima Carruth. and evergreen Quercus glauca Thunb. in warm-temperate forests in Jeju Island (Cheongsu; Seonheul) and cool-temperate forest at Chungnam National University Experimental Forest (CNU). Methods: Through an inter-site experiment and litterbag technique, variations in remaining mass and decomposition coefficients (k) were measured from the two Quercus species in Korea. Results: The initial mass loss was rapid during the wettest months in summer season. Annual k varied significantly by site: Seonheul (0.77 year−1 ± 0.03) > Cheongsu (0.62 year−1 ± 0.02) > CNU (0.42 year−1 ± 0.01). Leaf litter decomposition was similar for the two species in the warm-temperate sites and 36% higher in the deciduous species in the cool-temperate site. Based on the principal component analysis, overall k values were strongly correlated (rho = 0.55–0.60) with climatic factors, and no significant correlation was detected in leaf litter quality. Conclusion: In conclusion, our results highlighted that the climatic condition in the study sites predominantly controlled the litter decomposition of the deciduous and evergreen oak species, with nevertheless an interspecific difference in the coolest site. [ABSTRACT FROM AUTHOR]

The present study was conducted to identify the polymorphism of estrogen receptor (ESR) gene and its biological association with litter traits (litter size at birth, litter size at weaning, litter weight at birth and litter weight at weaning) of Doom pigs native to Assam. A total of 50 adult pigs (12 males and 38 females) chosen randomly from three different herds (Herd I, Herd II, and Herd III) were utilized in the present study. Detection of polymorphism of ESR gene was done by means of PCR-RFLP method. The amplified PCR product was digested with Pvu II restriction enzyme. PCR-RFLP analysis of ESR gene revealed polymorphic banding pattern. Two genotypes viz. AA and AB were identified. AA genotype yielded one fragment (120 bp) and AB genotype yielded three fragments (120, 65, and 55 bp). BB genotype was not found in the population under study. The frequencies ofA and B alleles were found to be 0.650 and 0.350, respectively, and the genotypic frequencies of ESR gene were found to be 0.300 and 0.700 for AA and AB genotypes, respectively. There was no significant (P > 0.05) effect of ESR genotype on litter traits and the population under study was not in Hardy-Weinberg Equilibrium for ESR gene. ClustalWMultiple alignment of partial sequence of ESR gene revealed single nucleotide changes at 33, 65, 70, 83, and 92nd nucleotide positions. The presence of Pvu II polymorphism and identification of single nucleotide variation of ESR gene opens interesting prospects for improvement of litter traits in Doom pig through selective breeding program, especially based on marker-assisted selection. [ABSTRACT FROM AUTHOR]

Pig farming is one of the most economically viable options for the rural backward and resource-poor farmers in Asian countries. Growth rate and litter size are the most important traits based on which the crossbreeding programs are typically planned in commercial pig farming. The modern system of farming with high yielding improved pig germplasm helps in economic growth in piggery enterprises. The present study was undertaken to evaluate the influence of various genetic and non-genetic factors on growth and reproductive performances of 75% crossbred progenies of Large White Yorkshire and indigenous Agonda Goan pigs. Body weights were recorded at birth, weaning, and at monthly intervals up to 10 months of age. Reproductive performances were also recorded for litter size and weights at birth and weaning stages, age at first farrowing, number of services per conception, farrowing interval, and pre-weaning mortality. The general linear model was used to estimate overall least square means of body weights at different ages considering the effects of different factors at certain levels viz., generation (i = first, second, third, fourth), sex (j = male, female), litter size at birth (k = 1–3, 4–6, 7–9, ≥10), parity (l = 1, 2, ≥3), season (m = summer, rainy, spring), and period of birth (n = 2012–2015, 2016–2019). The heritability and genetic correlations for different traits were estimated by restricted maximum likelihood (REML) method using WOMBAT software. The re(production) parameters were analyzed to assess the genetic improvement in successive generations. There was significant difference (p < 0.01) in body weights among different generations where animals belonging to latest generation showed maximum body weights indicating ideal selective breeding in the herd. Other fixed effects also had significant effects on growth performance which clearly signifies to the crucial influence of rearing environment and animal factors like parity of dams as well as litter size at birth. The overall birth weight, weaning weight, and weight at 10 months of age were 1.00 ± 0.01 kg, 7.57 ± 0.07 kg, and 81.58 ± 1.96 kg, respectively. Nevertheless, weaning weight and weight at marketing age (8 months) were 8.04 ± 0.27 kg and 75.48 ± 1.40 kg, respectively, in fourth generation, indicating higher post-weaning growth rate of 337.20 g/day. During this fourth generation, mean litter size at birth was 8.35 ± 0.43 and litter size at weaning was 7.79 ± 0.39 with lowest percentage of pre-weaning mortality (4.11 ± 1.51). The average age at first farrowing and farrowing interval was 293 ± 17.24 and 195 ± 4.78 days, respectively. There was apparently greater genetic gain in each generation except for the second generation which might be due to the environment and managemental issues that hindered reproductive performance traits and body growth. The heritability estimate for weaning weight was 0.45 and higher heritability values were observed for all the body weights except weight at third month. Genetic as well as phenotypic correlations were moderate to high among the growth traits. The heritability and genetic correlations at birth and weaning indicate the reliability of selection at an early age. The findings indicated that there is scope for improvement through genetic selection in later generations and the 75% crossbred pigs thrived well in the prevailing hot and humid tropical coastal climate. The improved germplasm could satisfy the farmers’ need in a commercial venture with high economic return. [ABSTRACT FROM AUTHOR]

Improvement in litter traits is the key to profitable pig farming that directly enhances the economic standing of the farmers in developing countries. The present study aimed to explore oestrogen receptor (ESR), epidermal growth factor (EGF), follicle‐stimulating hormone beta subunit (FSHβ), prolactin receptor (PRLR) and retinol‐binding protein 4 (RBP4) genes as possible candidate genetic markers for litter traits in indigenous pigs of India. The breeds included in the study were Ghungroo, Mali, Niang Megha and Tenyi Vo, and the reproductive traits considered were litter size at birth (LSB), number born alive (NBA), litter weight at birth (LWB), litter size at weaning (LSW) and litter weight at weaning (LWW) at their first parity. PCR‐RFLP and primer‐based mutation detection methods were used to identify polymorphism, and associations between the genotypes and the traits were analysed using a general linear model. The Ghungroo pigs recorded the best litter performances among the breeds (p <.05, LWB p <.01). Different alleles and genotypes of the genes under study were detected. Short interspersed nuclear element (SINE) −/− genotype of FSHβ revealed significantly higher litter traits (p <.05, LSB p <.01). The LWW was also found to be significantly influenced by ESR BB and AB, EGF AB and BB, and PRLR CC genotypes (p <.05). Although we did not find statistically significant and consistently superior litter traits with respect to different genotypes of other studied genes than genotype SINE −/− of the FSHβ, PRLR CC genotype demonstrated superior performances for all the litter traits. Our study revealed the FSHβ as a potential candidate genetic marker for litter traits in indigenous pig breeds of India. [ABSTRACT FROM AUTHOR]

At broad spatial scales, the factors regulating litter decomposition remain ambiguous, with the understanding of these factors largely based on studies investigating site‐specific single litter species, whereas studies using multi litter species mixtures across sites are rare.We exposed in microcosms containing single species and all possible mixtures of four leaf litter species differing widely in initial chemical and physical characteristics from a temperate forest to the climatic conditions of four different forests across the Northern Hemisphere for 1 year.Calcium, magnesium and condensed tannins predicted litter mass loss of single litter species and mixtures across forest types and biomes, regardless of species richness and microarthropod presence. However, relative mixture effects differed among forest types and varied with the access to the litter by microarthropods. Access to the microcosms by microarthropods modified the decomposition of individual litter species within mixtures, which differed among forest types independent of litter species richness and composition of litter mixtures. However, soil microarthropods generally only little affected litter decomposition.Synthesis. We conclude that litter identity is the dominant driver of decomposition across different forest types and the non‐additive litter mixture effects vary among biomes despite identical leaf litter chemistry. These results suggest that across large spatial scales the environmental context of decomposing litter mixtures, including microarthropod communities, determine the decomposition of litter mixtures besides strong litter trait‐based effects. [ABSTRACT FROM AUTHOR]

Data from 302 progeny in a heterogeneous population of rabbits were used to estimate the heritability and correlations (phenotypic and genetic) of pre-weaning litter traits (litter size at birth LSB, litter size at weaning LSW, litter weight birth LWB, litter weight at weaning LWW, kit weight birth KWB, and kit weight weaning KWW). Heritability estimates for litter size ranged from 0.16 (LSW) to 0.22 (LSB). LWB and LWW were more highly heritable (0.52 and 0.55 respectively) than KWB and KWW (0.36 and 0.25 respectively). The genetic (rG) and phenotypic (rP) correlations between litter size and litter weight at birth and weaning were 0.69 to 0.88 (rG) and 0.28 to 0.88 (rP). Generally, litter traits gave higher estimates than individual kit traits implying that selection criteria based on litter performance rather than on individual kit performance should be applied in genetic improvement of pre-weaning traits in rabbits raised in derived savanna zone. [ABSTRACT FROM AUTHOR]

The current study evaluated the influence of selection for litter size at birth on litter traits and milk yield of New Zealand White (NZW) rabbits. A totalof 2231 litters produced from 063does and 72 bucks were used to assess litter size at birth (LSB) and weaning (LSW), litter weight at birth (LWB), litter weight at 21 d (LW21) and litter weight at weaning (LWW),as well as mortality percentage (MOR%)from birth (total alive) till weaning age, milk yield at lactation intervals of 0–7 d (MY07), 7-14 d (MY14), 14-21 d (MY21), 21-28 d (MY28) and 0-28 d (TMY) and milk conversion ratio during 21 d of lactation (MCR021). Multi-trait animal model was used to data analysis using VCE6 programe. Estimates of heritability for litter traits were low and ranging from 0.05 for LSB to 0.14 for LWB. Also, estimates for milk yield traits were low and ranged from 0.08 for MY7 to 0.22 for MY21. The contrast among these generations were significant (P<0.05), favoring the selected generations over the base population. Estimates of genetic correlations between litter traits were positively and ranged from low (0.06) between LSW and LWB to moderate (0.51) between LWB and LW21. Genetic correlation between milk yield traits at different periods of lactation ranged from low (0.19) between MY7 and MY28 to high(0.84) between MY21 and TMY, while negative correlation between MY7 and TMY (-0.29). The accumulative correlated selection responses were positively and significant for litter traits and milk traits, while neagative and significant for MOR %, positive and non significant for MCR%. Conclusively,The selection of NZW does for litter size at birth could be efficient to improve litter traits and milk yield traits. [ABSTRACT FROM AUTHOR]

Biodiversity is a major driver of numerous ecosystem functions. However, consequences of changes in forest biodiversity remain difficult to predict because of limited knowledge about how tree diversity influences ecosystem functions. Litter decomposition is a key process affecting nutrient cycling, productivity, and carbon storage and can be influenced by plant biodiversity. Leaf litter species composition, environmental conditions, and the detritivore community are main components of the decomposition process, but their complex interactions are poorly understood. In this study, we tested the effect of tree functional diversity (FD) on litter decomposition in a field experiment manipulating tree diversity and partitioned the effects of litter physiochemical diversity and the detritivore community. We used litterbags with different mesh sizes to separate the effects of microorganisms and microfauna, mesofauna, and macrofauna and monitored soil fauna using pitfall traps and earthworm extractions. We hypothesized that higher tree litter FD accelerates litter decomposition due to the availability of complementary food components and higher activity of detritivores. Although we did not find direct effects of tree FD on litter decomposition, we identified key litter traits and macrodetritivores that explained part of the process. Litter mass loss was found to decrease with an increase in leaf litter carbon:nitrogen ratio. Moreover, litter mass loss increased with an increasing density of epigeic earthworms, with most pronounced effects in litterbags with a smaller mesh size, indicating indirect effects. Higher litter FD and litter nutrient content were found to increase the density of surface‐dwelling macrofauna and epigeic earthworm biomass. Based on structural equation modeling, we conclude that tree FD has a weak positive effect on soil surface litter decomposition by increasing the density of epigeic earthworms and that litter nitrogen‐related traits play a central role in tree composition effects on soil fauna and decomposition. [ABSTRACT FROM AUTHOR]

Litter decomposition mobilizes nutrients that sustain ecosystem productivity, but decomposition by‐products may also hamper root proliferation by phytotoxicity. The aim of this study was to assess the litter substrate preferences of tropical tree seedlings in relation to litter chemical traits. We characterized 44 litter types (11 species at four decomposition ages; 0, 30, 90 and 180 days) for nutrients (N, P, K, Mg, Mn, Na, Fe and Zn) and proximate chemical parameters (cellulose, extractive, lignin and C) and tested the effect of such litter materials on seedling root growth of Albizia procera, Dalbergia sissoo and Terminalia arjuna. Albizia procera root growth was inhibited by all litter types and ages, including conspecific materials, while different heterospecific litters had inhibitory or stimulatory effect on D. sissoo and T. arjuna root growth, compared to the control. Interestingly, inhibitory and stimulatory effects of heterospecific litters significantly changed with litter age, although with no clear‐cut pattern among target species and litter species and age, while conspecific litters consistently inhibited root growth when aged, but not when fresh. Litter nutrient, extractive, C, cellulose and lignin showed no consistent association with root growth of tested plants. Albizia procera root growth was positively associated with Na content and N:P ratio. Dalbergia sissoo root growth was positively associated to C:N and lignin:N ratios, and negatively to K, Na and Zn content. Finally, T. arjuna root was positively associated to cellulose and N:P ratio, but negatively to extractive. We conclude that studied nutrient, cellulose and lignin do not consistently explain the species‐specific response of root of tree seedlings to decomposing litter. [ABSTRACT FROM AUTHOR]

Plant litter decomposition is an essential ecosystem function in temperate streams. Both riparian vegetation and decomposer communities are major determinants of the decomposition efficiency and the interactions occurring within litter mixtures. However, the extent to which such litter mixture interactions are affected by combined shifts in litter traits and decomposer community is not well understood. We used leaf litter from 10 European tree species in order to study litter decomposition and litter mixture effects occurring in two-species litter mixtures in a temperate forested stream of northwestern France. The study distinguished between (1) decomposition involving microorganisms alone or together with invertebrates, and (2) decomposition involving litter mixtures of similar or dissimilar nutrient content. Increasing mean litter nutrient concentration favored both microbial activity and litter decomposition rate. Surprisingly, the highest litter mixture effects occurred in mixtures containing two nutrient-rich litters and occurred mainly in macroinvertebrate presence. Both the "mass ratio hypothesis," expressed as the community-weighted mean traits (TraitCWM), and the "niche complementarity hypothesis," expressed as the functional dissimilarity of litter traits (TraitFD), contributed to explain litter mixture effects. However, TraitCWM was found to be a better predictor than TraitFD. Finally, when evaluating the individual contributions of litter nutrients, calcium and magnesium appeared as important drivers of litter mixture effects. Our findings suggest that the mass ratio hypothesis overrules the niche complementarity hypothesis as a driver of litter diversity effects. Our study highlights the key importance of macroinvertebrates and of leaf nutrients, such as Ca and Mg, which are often neglected in decomposition studies in streams. [ABSTRACT FROM AUTHOR]

Land-use change in tropical forests can reduce biodiversity and ecosystem carbon (C) storage, but although changes in aboveground biomass C in human-modified tropical forests are well-documented, patterns in the dynamics and storage of C belowground are less well characterised. To address this, we used a reciprocal litter transplant experiment to assess litter decomposition and soil respiration under distinct litter types in forested or converted habitats in Panama, Central America, and in Sabah, Malaysian Borneo. The converted habitats comprised a large clearing on the Panama Canal and oil palm plantation in Borneo; forested habitats comprised a 60-year old secondary forest in Panama and a disturbed forest in Borneo that was selectively logged until 2008. In each habitat, we installed mesocosms and litterbags with litter collected from old-growth forest, secondary forest or an introduced species: Elaeis guineensis in Borneo and Saccharum spontaneum in Panama. We measured litter mass loss, soil respiration, and soil microbial biomass during nine months at each site. Decomposition differed markedly between habitat types and between forest vs. introduced litter, but the decay rates and properties of old-growth and secondary forest litters in the forest habitats were remarkably similar, even across continents. Slower decomposition of all litter types in the converted habitats was largely explained by microclimate, but the faster decay of introduced litter was linked to lower lignin content compared to the forest litter. Despite marked differences in litter properties and decomposition, there was no effect of litter type on soil respiration or microbial biomass. However, regardless of location, litter type, and differences in soil characteristics, we measured a similar decline in microbial activity and biomass in the absence of litter inputs. Interestingly, whereas microbial biomass and soil respiration increased substantially in response to litter inputs in the forested habitats and the converted habitat in Panama, there was little or no corresponding increase in the converted habitat in Borneo, indicating that soil recovery capacity had declined substantially in oil palm plantations. Overall, our results suggest that litter inputs are essential to preserve key soil processes, but litter diversity may be less important, especially in highly disturbed habitats.

Leaf litter decomposition rates (LDRs) of understory woody species vary substantially across species in temperate forest ecosystems. Using litter traits and LDR data for 78 shrub and liana species from a previous study, plus an additional litterbag experiment with varying mesh bag sizes for a subset of 17 species with rapid LDRs, we report that litter traits have nonlinear effects on LDR. In addition, we show that mesofauna, including nonnative earthworms, in general increase LDR and that the effects are greater for species of high LDR. Our results suggest that the acceleration of LDR by the co-invasion of plant species with high LDR and soil biota can promote nutrient cycling, potentially disrupting the stability of native forest ecosystems. [ABSTRACT FROM AUTHOR]

Comparison of the multi‐trait animal model and the traditional repeatability model was carried out using data obtained from 6,424 Landrace and 20,835 Yorkshire sows farrowed from January 2000 to April 2018 in order to estimate genetic parameters for litter traits at different parities. Specifically, records of the total number born (TNB), number born alive (NBA), total number of mortality (MORT), number of stillborn (NSB) and number of mummified pigs (MUM) were used. Although results showed the heterogeneity of heritability for litter traits at different parities, the mean heritability estimates from the multi‐trait model were found to be higher than those of the repeatability model for all traits in both pig breeds. In terms of genetic correlation between parities, a slight difference in genetic control in the first parity was noted for TNB and NBA in Landrace and Yorkshire pigs. The correlation between the first parity and later parities ranged from 0.48 to 0.74 for TNB and NBA in both breeds. Moreover, genetic correlation between parities for MORT and NSB was observed to be high for parities higher than 2 in Yorkshire pigs. For MUM, genetic correlation between the first and other parities was generally low in both breeds, indicating that culling pigs on the basis of MUM at the first parity could probably be unreasonable. Overall, the results of this study suggest that the multi‐trait approach for litter size traits is useful for the accurate estimation of genetic parameters. [ABSTRACT FROM AUTHOR]

Leaf litter decomposition is a key component of global biogeochemical cycles that influence soil carbon storage, nutrient availability and plant productivity. Ongoing climate change will lead to warmer and drier conditions in many dryland regions, potentially affecting litter decomposition and nutrient dynamics. Climate change effects can be direct and/or indirect, for example, through changes in litter quality, yet their relative importance on litter decomposition remains unclear.We conducted a manipulative study in a semi‐arid shrubland to assess the effects of leaf litter quality, forecasted climate change, that is, +2.5°C warming (W), 30% rainfall reduction (RR) as well as their interaction (W + RR) to elucidate their relative effects on litter decomposition.Climatic effects alone reduced decomposition of a homogeneous Control leaf litter collected from Helianthemum squamatum shrubs growing in unmanipulated plots by 23.4%, 18.1% and 29.8% in the W, RR and W + RR treatments respectively. Leaf litter quality was lower in shrubs that had been growing in warmed plots (W and W + RR), as they had lower nutrient concentrations (P, Fe) and higher C:N and C:P ratios than leaf litter produced under ambient (Control) conditions. Lignin concentration was significantly lower in litter from W + RR plots, yet when both climate and litter quality were considered simultaneously, decomposition rates were 32.0%, 26.3% and 39.9% lower in W, RR and W + RR plots compared to Controls. In addition, we found greater microbial N immobilization in leaf litter incubated within warmed (W and W + RR) than within non‐warmed plots (Control and RR). Structural equation modelling showed that higher litter moisture and microbial biomass contents stimulated decomposition. Simulated climate change (W, RR and W + RR) reduced decomposition indirectly by negatively affecting litter moisture contents and litter microbial biomass. Microbial nitrogen immobilization was stimulated by the lower quality (i.e. high C:N ratios) of the leaf litter collected in shrubs from warmed plots (W and W + RR).Synthesis. Our findings indicate that forecasted climate change conditions slow down C and N cycling in a dryland ecosystem, an effect that is further exacerbated by climate change‐induced reductions in litter quality and related reductions in bacterial and fungal biomass in litter. [ABSTRACT FROM AUTHOR]

This study was done inside an assignment that intended to break down options and strategies for the progression of a rabbit line by using two pure breeds (V-line (V), and Gabali (G)). Records of 448 packs delivered by 45 does and 16 bucks were utilized to estimate covariance, Heritability (h2), genetic and phenotypic correlations, and breeding values of litter traits were evaluated in composite of crossbreeding arrangement of ten mating groups. The initial five groups comprise of (G♂ X V♀) and reciprocal crosses (V♂ X G♀) for the other five groups. Each buck was represented as a sire to all litters in each group to create F1 (½G ½V& ½ V½G sire breed is demonstrated first) for four parities. Weaning was performed at 28 days of kits age. Pre-weaning litter traits were measured (for instance, litter size at both birth (LSB), and at weaning (LSW); litter weight either at birth (LWB), and body weight at weaning (BWW)). Data were examined utilizing GLM and VARCOMP procedures of SAS took after by single and multi-trait animal model investigations (AM), which performed utilizing derivate free limited maximum likelihood (MTDFREML). The results revealed that h2 estimates for LSB and LSW were 0.133±0.01 and 0.15±0.063, respectively. The evaluations of coefficient of inconstancy (CV%) are 34.78% for LSB versus 39% for LSW, and 28.27% for LWB versus 33.53 % for BWW. The impact of mating groups on LSB and LSW, LWB and BWW had exceptionally significant being 7.921, 5.320, 0.402, and 0.450 kg for LSB, LSW, LWB and BWW for (G♂ X V♀), individually, while the proportional (V♂ X G♀) were 6.224, 4.80, 0.360, and 0.490 kg, separately. Parity significantly affected LSB, LWB, and BWW. Meanwhile, the impact of doe within buck as a random impact demonstrated an unacquainted impact altogether influenced all analyzed traits. Negative genetic correlation between litter size at birth and each of litter weight at birth and body weight at weaning. Additionally, environmental correlation between litter size at weaning and litter weight at birth was positive, while the environmental correlation between litter size at waning and body weight at weaning was negative but not significant. Furthermore, the precision of the evaluations of bucks breeding value (0.37 to 0.92) was higher than the exactness of doe (0.27 to 0.88) and progeny (0.36 to 0.85), which might be because of the higher number of descendants per buck. Subsequently, the outcomes demonstrated the significance of utilizing bucks of Gabali in rearing project to build the genetic advance. [ABSTRACT FROM AUTHOR]

In this study, the GnRHR gene polymorphism of the giant panda was detected, and its effects on litter size were analyzed. Thirty-eight giant pandas that were fed under similar conditions were randomly chosen, and polymorphism in the giant panda GnRHR gene coding region was detected by PCR-SSCP. The association between the GnRHR genotypes and litter size traits was carried out with the GLM procedure using the SAS software. The PCR-SSCP test results showed that the T516121C SNP locus existed in the GnRHR gene exon 1, the C504498T SNP locus existed in exon 2, but no SNP locus was found in exon 3. The T516121C and C504498T loci belong to the non-synonymous mutations. The T516121C substitution led to one amino acid mutation (Cys>Arg), as did the C504498T substitution (Ala>Val). In the group of 38 pandas, there were three genotypes at the T516121C and C504498T loci. The chi-square test showed that the T516121C and C504498T loci fit into the Hardy Weinberg equilibrium in the giant panda population (P>0.05). Furthermore, the correlation analysis results indicated that the different genotypes of the C504498T locus in the panda GnRHR gene had significant effects on the average litter size for second births (P=0.05). The average litter size for second births of giant pandas with the CC genotype was higher than that the size of the DD genotype (P=0.05). The first births of the giant pandas with the AA genotype had the maximum average litter size, and there was no significant correlation between the T516121C loci with litter size traits of giant panda. Therefore, these results suggest that the C504498T base mutation in the exon 2 of GnRHR could influence the litter size of giant panda. In other words, GnRHR could influence fertility in giant panda. [ABSTRACT FROM AUTHOR]

Rates of leaf litter decomposition in streams are strongly influenced both by inorganic nutrients dissolved in stream water and by litter traits such as lignin, nitrogen (N) and phosphorus (P) concentrations. As a result, decomposition rates of different leaf species can show contrasting responses to stream nutrient enrichment resulting from human activities. It is unclear, however, whether the root cause of such discrepancies in field observations is the interspecific variation in either litter nutrient or litter lignin concentrations. To address this question, we conducted a controlled laboratory experiment with a known fungal community to determine decomposition rates of 38 leaf species exhibiting contrasting litter traits (N, P and lignin concentrations), which were exposed to 8 levels of dissolved N concentrations representative of field conditions across European streams (0.07 to 8.96 mg N L−1). The effect of N enrichment on decomposition rate was modelled using Monod kinetics to quantify N effects across litter species. Lignin concentration was the most important litter trait determining decomposition rates and their response to N enrichment. In particular, increasing dissolved N supply from 0.1 to 3.0 mg N L−1 accelerated the decomposition of lignin-poor litter (e.g. < 10% of lignin, 2.9× increase ± 1.4 SD, n = 14) more strongly than that of litter rich in lignin (e.g. > 15% of lignin, 1.4× increase ± 0.2 SD, n = 9). Litter nutrient concentrations were less important, with a slight positive effect of P on decomposition rates and no effect of litter N. These results indicate that shifts in riparian vegetation towards species characterized by high litter lignin concentrations could alleviate the stimulation of C turnover by stream nutrient enrichment. [ABSTRACT FROM AUTHOR]

Highlights • Litter identity and predator density regulate tri-trophic interactions (Fungi - fungivorous Collembola - predatory Acari) in forest ecosystems. • Pine litter favors fungi and Acari whereas oak litter favors Collembola. • High predator density negatively affects both Collembola and Acari demographic parameters. Abstract Plant litter decomposition is an essential process of ecosystem functioning, driven by a complex soil food web. The identity and density of the predators, as well as the quality and quantity of litter, could conjointly affect the strength of trophic interactions within a soil food web. Pine and oak are dominant tree species in temperate and Mediterranean forests and, although they exhibit distinct litter characteristics, no previous study attempted to decipher how these two litters can affect a litter-based multi-trophic system with varying predator density. Using a microcosm experiment, we aimed at understanding how different densities of a predatory Acari (Stratiolaelaps scimitus) and two Mediterranean litter species (Quercus pubescens and Pinus halepensis) may impact the demographic parameters of the predatory Acari, its Collembola prey (Folsomia candida) and the fungal biomass associated with litter. We did not observe any interactive effect of litter identity and predator density on both predator and prey demographic parameters. Survival and fecundity rates of the predator and its prey decreased at high predator density. However, demographic parameters of the predator and its prey were differentially affected by litter identity, with greater prey demographic parameters in Quercus litter and, in the opposite, greater predator demographic parameters in Pinus litter, probably due to differences in physical characteristics providing more or less refuge for the prey. We also observed a higher increase in fungal biomass in Pinus compared to Quercus litter, i.e. the litter with the fungivorous Collembola abundance reduced by the predatory Acari. Litter identity could thus strongly regulate these tri-trophic interactions (Fungi – fungivorous Collembola – predatory Acari) in forest ecosystems. Finally, the implications of our findings could be important as the distribution area of oak and pine forests may be altered in response to climate change with then potentially strong cascading effects on soil organisms and the processes they drive. [ABSTRACT FROM AUTHOR]

Aim: The present study was carried out at Institute Rabbit Farm of Southern Regional Research Centre, Mannavanur, Kodaikanal, Tamil Nadu, India having sub-temperate climate with winter temperature during night hours going below 0°C with an objective of finding the influence of different factors such as breed, year, season and parity on different reproductive traits of broiler rabbits in order to come out with the best strategies for improving the productivity. Materials and Methods: A total of 1793 records (946 White Giant and 847 Soviet Chinchilla) for weight at mating (WM), weight at kindling (WK), gestation length (GL), litter size at birth (LSB) and litter size at weaning (LSW), litter weight at birth (LWB), and litter weight at weaning (LWW) were collected in the period between 2000 and 2009 and the data was analyzed using general linear model option of SAS 9.2. Results: The overall mean GL, WM, WK, LSB, LSW, LWB, and LWW were 31.68±0.04 days, 3.65±0.01 kg, 3.84±0.01 kg, 6.91±0.08, 5.49±0.09, 387.62±4.07 g, and 4.66±0.07 kg, respectively. The breed has significantly influenced GL, WK, LSW, LWB, and LWW. The LSB, LSW, LWB, and LWW were 7.05±0.11, 5.76±0.13, 399.55±5.88 g, and 4.87±0.10 kg, respectively in White Giant and corresponding values for Soviet Chinchilla were 6.78±0.11, 5.22±0.12, 375.91±5.64 g, and 4.46±0.09 kg, respectively. The year of kindling had significantly affected all the reproductive traits under study and is varying over different years. The parity significantly influenced the WM, WK, and LWW. The LWW increased from first (4.16±0.21 kg) to second parity (4.86±0.19 kg) and remained in the same range from third parity onward. WM was significantly higher in spring season (3.72±0.02) than the animals in rainy (3.59±0.02) and winter season (3.65±0.02). Better reproductive performance in terms of higher LSB, LSW, LWB, and LWW as observed in the present study might be due to conducive environmental conditions prevailing in the region. Conclusion: The significant effects of the non-genetic factors like year of kindling on all reproductive traits, season, and parity on some of the traits in rabbit breeds are indications that any future production enhancement strategy must take into consideration the environment by providing additional care, feed supplementation and better shelter management to the rabbits, so that the full genetic potential can be realized.

Background and aims: Home-field advantage (HFA) hypothesis predicts that plant litter decomposes faster beneath the plant species from which it was derived than beneath other plant species. However, it remains unclear, which groups of soil organisms drive HFA effects across a wide range of litter quality and forest types.Methods: We set up a reciprocal transplant decomposition experiment to quantify the HFA effects of broadleaf, coniferous and bamboo litters. Litterbags of different mesh sizes and high-throughput pyrosequencing of microbial rRNA gene were used to test the contribution of different decomposer groups to HFA effect.Results: The recalcitrant broadleaf litter and the labile bamboo litter exhibited HFA. Presence of meso-and macrofauna did not substantially change the HFA effects. Bacterial and fungal community composition on litters were significantly influenced by litter type. Bacterial community composition remained unchanged when the same litter was decomposed in different forest types, whereas fungal community composition on broadleaf and bamboo litters were significantly influenced by incubation site.Conclusions: Our data demonstrate specific association between fungal community composition and faster litter decomposition in the home site, suggesting that fungi probably participate in driving the HFA effect of broadleaf and bamboo litters. [ABSTRACT FROM AUTHOR]

Total number born (TNB), number born alive (NBA), and litter weight born alive (LWB) are critically important traits in pig production. The sow's parity is one of the major factors influencing litter traits. Because of monogenic or polygenic contributions and the presence of temporal gene effects in different sows' parities, it is difficult to clarify the biological and genetic background. To systematically explore the genetic mechanism of litter traits, we conducted 18 GWASs using single-step GWAS (ssGWAS) based on two breeds (908 Landrace and 1,130 Large White sow litter records) for each litter trait in different parities. A total of 300 Landrace and 300 Large White sows were genotyped by sequencing (GBS). ssGWAS was performed separately for each breed and each parity due to population stratification and temporal gene effect. In summary, we identified 80 (15 for Landrace and 65 for Large White), 227 (52 for Landrace, 175 for Large White), and 187 (34 for Landrace, 153 for Large White) single nucleotide polymorphisms (SNPs) affecting TNB, NBA, and LWB, respectively. Of them, we suggest that a total of 22 loci (SSC1: 125098202, SSC1: 117560058, SSC14: 147794697, SSC8: 84823302, SSC9: 143554876, and SSC9: 138766097 for Landrace; SSC1: 4023577, SSC1: 3859573, SSC1: 4891063, SSC16: 5197665, SSC10: 32050819, SSC13: 13552924, SSC13: 92819, SSC17: 3579607, SSC13: 196698221, SSC7: 30918403, SSC16: 46221484, SSC16: 46169204, SSC2: 41988642, SSC2: 44475457, SSC2: 42521875, and SSC7: 58411951 for Large White) are shared by TNB, NBA, and LWB. These results indicate the existence of gene temporal effect in each parity. Furthermore, our findings suggest four interesting candidate genes (FBXL7, ALDH1A2, LEPR, and DDX1) associated with litter traits in different parities that have a major effect on embryonic development progression. In conclusion, 22 crucial SNPs and four interesting candidate genes were identified for three litter traits across six parities. These findings advance our understanding of the genetic architecture of litter traits and confirm the presence of temporal gene effects in different parities. Importantly, functional validation studies for findings of particular interest are recommended in litter traits. [ABSTRACT FROM AUTHOR]

In many terrestrial ecosystems, detritivorous soil organisms ingest large amounts of leaf litter returning most of it to the soil as faeces. Such conversion of leaf litter into faeces may stimulate decomposition by increasing the surface area available for microbial colonisation. Yet, experimental support for either the outcome or the mechanism of these conversion effects is lacking.Based on the hypothesis that the identity of plant species from which leaf litter is transformed into faeces has a critical role in how faeces decomposition proceeds, we collected faeces of the widely abundant millipede Glomeris marginata fed with leaf litter from seven distinct tree species. We compared the physical and chemical characteristics and the rates of carbon (C) and nitrogen (N) loss between litter and faeces.We found that after 100 days of exposure under controlled conditions, C loss was on average higher in faeces (40.0%) than that in litter (26.6%), with a significant increase for six of the seven species. Concurrently, N dynamics switched from a net immobilisation (7.7%) in litter to a net release (14.6%) in faeces, with a significant increase for five of the seven species.Litter conversion into faeces generally homogenised differences in physical and chemical characteristics among species. Despite such homogenisation, variability in rates of faeces C and N loss among species was similar compared to leaf litter, but correlated with a different set of traits. Specifically, faecal pellet C loss was positively related to compaction (decreased specific area and increased density of faecal pellets), and both C and N loss from faecal pellets were positively related to fragmentation (increased specific area and perimeter of particles within faecal pellets).We conclude that litter fragmentation and compaction into detritivore faecal pellets lead to substantially enhanced decomposition, with a particularly strong impact on N dynamics that changed from immobilisation to net release depending on litter species. Moreover, litter quality control on decomposition is reshuffled by litter conversion into faeces. In ecosystems with high detritivore abundance, this so far largely overlooked pathway of organic matter turnover may strongly affect ecosystem C and N cycling. A plain language summary is available for this article. Plain Language Summary [ABSTRACT FROM AUTHOR]

Abstract: Genetic parameters and trends in the average daily gain (ADG), backfat thickness (BF), loin muscle area (LMA), lean percentage (LP), and age at 90 kg (D90) were estimated for populations of Landrace and Yorkshire pigs. Additionally, the correlations between these production traits and litter traits were estimated. Litter traits included total born (TB) and number born alive (NBA). The data used for this study were obtained from eight farms during 1999 to 2016. Analyses were carried out with a multivariate animal model to estimate genetic parameters for production traits while bivariate analyses were performed to estimate the correlations between production and litter traits. The heritability estimates were 0.52 and 0.43 for ADG; 0.54 and 0.45 for BF; 0.25 and 0.26 for LMA; 0.54 and 0.48 for LP; and 0.56 and 0.46 for D90 in the Landrace and Yorkshire breeds, respectively. The ADG and D90 showed low genetic correlation with BF and LP. The LMA had −0.40, −0.32, 0.49, and 0.39 genetic correlations with ADG, BF, LP, and D90, respectively. Genetic correlations between production and litter traits were generally low, except for the correlations between LMA and TB (−0.23) in Landrace and ADG and TB (−0.16), ADG and NBA (−0.18), D90 and TB (0.19), and D90 and NBA (0.20) in Yorkshire. Genetic trends in production traits were all favorable except for LMA. [ABSTRACT FROM AUTHOR]

Tree species diversity of forested ecosystems control the diversity of leaf litter inputs to the soil, with cascading effects on the microbial communities colonizing decomposing litter. However, the extent to which bacterial and fungal communities inhabiting the litter layer are affected by shifts in tree species diversity is not well understood. To investigate the role of litter species diversity, litter species identity and litter functional traits on bacterial and fungal communities of a typical Mediterranean oak forest, we set up a yearly field litterbag experiment that considered leaf litter mixtures of four abundant species: Quercus pubescens , Acer monspessulanum , Cotinus coggygria and Pinus halepensis . We found that both bacterial and fungal communities varied strongly during decomposition but showed distinct succession patterns. Both communities were also strongly influenced by litter species diversity, litter identity and litter functional traits. The intensity and the direction of these effects varied during decomposition. Litter diversity effects were mediated by litter species composition rather than litter species richness, highlighting the importance of litter species identity - and associated litter traits - as drivers of microbial communities. Both the “mass-ratio hypothesis”, measured through the community weighted mean (CWM) litter traits, and the “niche complementarity hypothesis”, measured through the functional dissimilarity (FD) of litter traits, contributed to litter diversity effects, with a greater relative importance of FD compared to CWM, and with an overall stronger impact on fungal- than on bacterial-communities. Interestingly, increasing FD was related to decreasing bacterial diversity, but increasing fungal diversity. Our findings provide clear evidence that any alteration of plant species diversity produces strong cascading effects on microbial communities inhabiting the litter layer in the studied Mediterranean oak forest. [ABSTRACT FROM AUTHOR]

Background & Aims: Oak seedling establishment is difficult and may be partly explained by litter-mediated interactions with neighbors. Litter effects can be physical or chemical and result in positive or negative feedback effects for seedlings. Mediterranean species leaves contain high levels of secondary metabolites which suggest that negative litter effects could be important.Methods: Seedlings of Quercus ilex and Quercus pubescens were grown for two years in pots with natural soil and litter inputs from 6 Mediterranean woody species, artificial litter (only physical effect) or bare soil.Results: Litter types had highly different mass loss (41-80%), which correlated with soil organic C, total N and microbial activity. Litter of Q. pubescens increased soil humidity and oak seedlings aerial biomass. Litters of Cotinus coggygria and Rosmarinus officinalis, containing high quantities of phenolics and terpenes respectively, decomposed fast and led to specific soil microbial catabolic profiles but did not influence oak seedling growth, chemistry or mycorrhization rates.Conclusions: Physical litter effects through improved soil humidity seem to be predominant for oak seedling development. Despite high litter phenolics content, we detected no chemical effects on oak seedlings. Litter traits conferring a higher ability to retain soil moisture in dry periods deserve further attention as they may be critical to explain plant-soil feedbacks in Mediterranean ecosystems. [ABSTRACT FROM AUTHOR]

The economic efficiency of mink production is greatly influenced by reproductive performance. Therefore, the objective of this study was to estimate phenotypic and genetic parameters for reproduction traits including total number of kits born (TB), number of live kits at birth (LB), number of live kits at weaning (LW), survival rate at birth (SB), survival rate at weaning (SW), gestation length (GL), average kit weight per litter at birth (AWB), average kit weight per litter at week 3 (AW3), and average kit weight per litter at weaning (AWW) in American mink. Data included records of 3,046 litters collected by the Canadian Centre for Fur Animal Research at Dalhousie Faculty of Agriculture between 2002 and 2016. Significance (P < 0.05) of fixed effects (year, number of matings, color type, age of dam, origin of dam, sex ratio, and number of live kits) and random effects of permanent environment were determined using univariate repeatability models. A significant effect of permanent environment was only found for survival rate traits (P < 0.05). Subsequently, genetic and phenotypic parameters for all traits were estimated by fitting a set of bivariate models using ASREML 4.0. Heritabilities (± SE) were estimated to be 0.07 ± 0.03 for TB, 0.07 ± 0.02 for LB, 0.09 ± 0.04 for LW, 0.13 ± 0.03 for SB, 0.10 ± 0.02 for SW, 0.29 ± 0.03 for GL, 0.28 ± 0.05 for AWB, 0.19 ± 0.04 for AW3, and 0.10 ± 0.04 for AWW. Moderate positive genetic correlation was observed between AWB with SB (0.66 ± 0.10) and SW (0.61 ± 0.13). Furthermore, genetic correlations of LB with SW and AWB were 0.55 ± 0.16 and 0.53 ± 0.18, respectively. On the other hand, negative and moderate genetic correlations were observed between GL and survival rates at birth (−0.43 ± 0.14) and at weaning (−0.37 ± 0.15). These results indicated that selection for higher litter weights at birth can effectively improve survival rate and number of live kits in mink farms. It was suggested to incorporate litter weight traits as a selection criterion to increase maternal ability in mink breeding programs. Unfavorable genetic trends were observed for the studied traits indicating that phenotypic selection with low selection intensity had not been an efficient method to improve them over the last 10 yr. It was recommended to use genetic or genomic evaluation methods for mink selection. [ABSTRACT FROM AUTHOR]

In this study, data genotyping by sequence (GBS) was used to perform single step GWAS (ssGWAS) to identify SNPs associated with the litter traits in domestic pigs and search for candidate genes in the region of significant SNPs. After quality control, 167,355 high-quality SNPs from 532 pigs were obtained. Phenotypic traits on 2112 gilt litters from 532 pigs were recorded including total number born (TNB), number born alive (NBA), and litter weight born alive (LWB). A single-step genomic BLUP approach (ssGBLUP) was used to implement the genome-wide association analysis at a 5% genome-wide significance level. A total of 8, 23 and 20 significant SNPs were associated with TNB, NBA, and LWB, respectively, and these significant SNPs accounted for 62.78%, 79.75%, and 58.79% of genetic variance. Furthermore, 1 (SSC14: 16314857), 4 (SSC1: 81986236, SSC1: 66599775, SSC1: 161999013, and SSC1: 267883107), and 5 (SSC9: 29030061, SSC2: 32368561, SSC5: 110375350, SSC13: 45619882 and SSC13: 45647829) significant SNPs for TNB, NBA, and LWB were inferred to be novel loci. At SSC1, the AIM1 and FOXO3 genes were found to be associated with NBA; these genes increase ovarian reproductive capacity and follicle number and decrease gonadotropin levels. The genes SLC36A4 and INTU are involved in cell growth, cytogenesis and development were found to be associated with LWB. These significant SNPs can be used as an indication for regions in the Sus scrofa genome for variability in litter traits, but further studies are expected to confirm causative mutations. [ABSTRACT FROM AUTHOR]