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The objective was to characterize the effects of a supplemental Herbal Antibiotics Source (HAnS) on performance, blood chemistry, blood cells, and antibody counts of Holstein calves. Forty calves (initial BW 45.8 ± 7.2 kg) were randomly assigned to treatments: 0, 3, 4, and 5 g d−1 HAnS. The additive improved hip height and thoracic girth. The reduction of starter diet intake among individuals varied greatly, while milk replacer intake increased. HAnS at intermediate doses reduced the cases of pneumonia. It also linearly reduced the blood serum glucose and B-OH butyrate. Urea and monocytes showed a quadratic response, and basophils decreased. HAnS improves calf development at intermediate doses and reduces the incidence of diseases.

The objective of this experiment was to evaluate the effects of feeding different levels concentrations of dietary calcium propionate (CaPr) on lambs’ growth performance, ruminal fermentation parameters, glucose–insulin concentration, and hypothalamic mRNA expression for neuropeptide Y (NPY), agouti-related peptide (AgRP), and proopiomelanocortin (POMC). Thirty-two individually fed lambs were randomly assigned to four treatments: (1) control diet (0 g/kg of CaPr), (2) low CaPr, (30 g/kg dry matter (DM)), (3) medium CaPr, (35 g/kg DM), and (4) high CaPr (40 g/kg DM). After 42 days of feeding, lambs were slaughtered for collecting samples of the hypothalamus. Data were analyzed as a complete randomized design, and means were separated using linear and quadratic polynomial contrast. Growth performance was not affected (p ≥ 0.11) by dietary CaPr inclusion. The ruminal concentration of total volatile fatty acids (VFA) increased linearly (p = 0.04) as dietary CaPr increased. Likewise, a linear increase in plasma insulin concentration (p = 0.03) as dietary CaPr concentration increased. The relative mRNA expression of NPY exhibited a quadratic effect (p &lt, 0.01), but there were significant differences in the mRNA expression of AgRP and POMC (p ≥ 0.10). Dietary calcium propionate did not improve lamb growth performance in lambs feed with only forage diets. Intake was not correlated with feed intake with mRNA expression of neuropeptides.

Background: The effects of the probiotics vary with the doses and strains used for this reason, a study was conducted over 35 days to determine the effect of live yeast supplementation in the diet of growing rabbits on growth performance and apparent nutrient digestibility.Methods: A total of 60 New Zealand and California rabbits (5 weeks old, average body weight 0.881±0.015 kg) were housed in 30 cages. They were fed with a control diet based on alfalfa and maize or barley grains and supplemented with Procreatin®7 (Saccharomyces cerevisiae CNCM I 1077) or Biosaf® SC47 (Saccharomyces cerevisiae NCYC Sc47) at three doses, namely 0, 6.4, or 12.8 ×109 CFU per kg basal diet.Result: The higher yeast concentration had a positive effect (P less than 0.01) on final body weight (BW), average daily gain (ADG) and carcass weight (CW). However, there were no significant differences in dry matter intake. As a result of this, the feed conversion ratio (FCR) decreased (P less than 0.01). Significant increases (P less than 0.05) in nutrient digestibility (DM, OM, NDF and ADF) were observed with both grains. The use of yeast in maize and barley-based diets of rabbits has positive effects on growth performance and nutrient digestibility.

We evaluated current uses of wild mammals by indigenous and mestizo communities in Mexico by extracting data from 59 sources published or produced between 1987–2017, covering data from 240 localities and 3,905 questionnaires. We then calculated a Cultural Value Index (CVI) previously applied to plants to quantify resource use and assess the cultural significance of each mammal. A total of 82 species were reported, and the animals with the highest cultural importance according to their CVI (in brackets) were two species of deer (Odocoileus virginianus [18.32] and Mazama temama [10.04]), as well as the nine-banded armadillo (Dasypus novemcinctus [14.18]), white-nosed coati (Nasua narica [14.75]), collared peccary (Pecari tajaccu [11.90]), northern raccoon (Procyon lotor [11.28]) and spotted paca (Cuniculus paca [9.84]). The most common uses were for food, to reduce the damage or harm they cause, and for medicinal purposes, with O. virginianus, P. lotor, N. narica, and D. novemcinctus frequently hunted for all these reasons. Our analysis also highlighted the hunting of rarer species of national conservation concern, including commercial trading of body parts of the felids Panthera onca, Leopardus pardalis, and Leopardus wiedii. By quantifying the ethnozoological significance of wildlife to indigenous communities, indices such as CVI provide a robust measure of the extent of use and preference for particular species or taxa. This adds to the body of evidence used to develop effective regulations and laws related to harvesting and hunting, and helps promote a more sustainable and long-term approach to the use of natural resources.

To evaluate phenolic compounds and whether the combination of a tanniferous fruit and soybean oil could improve the performance, meat characteristics, and fatty acid (FA) profile in lambs, an experiment was conducted over 40 days with twenty creole male lambs (23.71±3.46 kg). The lambs were allotted in a completely randomised design, with factorial arrangement 2 × 2, with the following dietary treatments: (1) control diet, (2) 2%Caesalpinia coriariaground fruit dry matter (DM), (3) 2% soybean oil DM, and (4) 2%Caesalpinia coriariafruit plus 2% soybean oil. The concentration of condensed tannins (CT) inCaesalpinia coriaceawas 21.71 g/kg DM. No interactions were detected (P>0.05) among soybean oil andCaesalpinia coriaria, and there were no differences in daily gain, intake, and feed conversion. Soybean oil reduced (P<0.05) DM digestibility (68.05 versus 59.56%). In fat from thelongissimus thoracis et lumborum(LTL) muscle, only linoleic acid presented differences (P<0.05) between treatments. The combination ofCaesalpinia coriaceafruit and soybean oil did not improve lamb performance at the included levels.

The study was carried out in a median stature tropical forest in the north of Quintana Roo during 2008, 2010-2012, using camera traps to record activity and habitat use by jaguar and other vertebrates. Spatial and temporal variations in habitat use, activity patterns, and species associations were analyzed using a chi-squared test (x2). Generalized\ud linear models (GLM) were used to determine which variables influenced the presence of jaguars in the study area. Jaguars were most frequently recorded in acahual (80%) and on roads (66.9%). There were significant differences between years, with selection for particular habitat and trail types in 2008 and 2011 (all χ2 p

11 páginas, 6 tablas., The effect of feeding two levels of Saccharomyces cerevisiae on the performance of crossbred Friesian calves was investigated. Twenty-four neonatal male Friesian × Baladi calves (35·5 ± 0·25 kg of initial body weight) were randomly assigned in a completely randomized design into three experimental groups for 90 days (eight calves per group). Calves fed their diets without yeast (S. cerevisiae) were considered as Control, while the diets of other calves were supplemented daily either with 2·5 g (YL diet) or with 5 g (YH diet) of yeast per calf. Calves fed the YH diet showed increased feed intake, while dry matter and fibre digestibilities were increased in calves fed YH and YL diets. Calves fed YL and YH diets showed lower ruminal ammonia-N and higher total volatile fatty acids, acetate and propionate concentrations than Control calves. Both YH and YL calves showed increased plasma concentrations of total protein, globulin and glucose and decreased cholesterol and triglycerides concentrations. Calves' final weight and daily gain were increased with S. cerevisiae yeast supplemented diets. After 42 days of experiment, Clostridium spp., Escherichia coli and Enterobacteria spp. counts were down to undetectable levels in the faeces of calves fed S. cerevisiae additive. It could be concluded that adding S. cerevisiae to milk-fed calves increased feed utilization and improved pre-weaned calf performance and health status, reducing faecal pathogenic bacteria. Copyright © Cambridge University Press 2016.

Activity patterns have been explained as one of the axes that allow the niche segregation, which helps explain the coexistence of species, researchers have overlooked the relevance of these and their effects on the community dynamics. At northern Quintana Roo, Mexico, activity patterns of jaguar ( Panthera onca ), puma ( Puma concolor ) and 18 potential preys were evaluated by camera trapping in 2008, 2010 - 2012. The objectives were determining the overlap in circadian cycles between pumas, jaguars and potential prey to know if their activity patterns change over time. For the study only independent records of all species were considered, the overlap in activity patterns was evaluated using the coefficient of overlap ( d ). Bootstrap confidence intervals for coefficient of overlap were calculated at 95 % level based on 1,000 bootstrap replicates of the observed overlap coefficient. It is assumed that the activity data are generated by a circular distribution; thus activity patterns between pairs of species were compared by the nonparametric statistical test of Watson and Wheeler. Both predators were active throughout the day but are primarily nocturnal-twilight with estimated overlap coefficient of 0.87, their activity patterns changed over the years, factors like human activity and fair near to the reserve affect the activity, this factors modified the activity of both cats. Both cats had a temporal association with seven potential preys. The temporal segregation was given by the peaks of activity and spatial evasion. This study allows us understand temporal segregation strategies between felines and the factors that influencing changes in their activity patterns, although both cats have a high overlap in time. A detailed analysis shows that they modified their activity patterns through the years, this resulted after changes in the environment (human activity, fair near to the reserve, distribution and abundance prey), and this in turn causes a change in activity patterns of both felines evading each other.

We describe a technique to semichronically record the cortical extracellular neural activity in the behaving monkey employing commercial high-density electrodes. After the design and construction of low cost microdrives that allow varying the depth of the recording locations after the implantation surgery, we recorded the extracellular unit activity from pools of neurons at different depths in the presupplementary motor cortex (pre-SMA) of a rhesus monkey trained in a tapping task. The collected data were processed to classify cells as putative pyramidal cells or interneurons on the basis of their waveform features. We also demonstrate that short time cross-correlogram occasionally yields unit pairs with high short latency (

Many animals can encode temporal intervals and use them to plan their actions, but only humans can flexibly extract a regular beat from complex patterns, such as musical rhythms. Beat-based timing is hypothesized to rely on the integration of sensory information with temporal information encoded in motor regions such as the medial premotor cortex (MPC), but how beat-based timing might be encoded in neuronal populations is mostly unknown. Gámez and colleagues show that the MPC encodes temporal information via a population code visible as circular trajectories in state space; these patterns may represent precursors to more-complex skills such as beat-based timing., Many animals can encode temporal intervals, but only humans can flexibly extract a regular beat from complex patterns. This Primer explores recent insights into how rhythm and beat are encoded in the brain.

Jaguar (Panthera onca) and puma (Puma concolor) diets in Quintana Roo, Mexico. A study was carried out for two years in Northwest Quintana Roo, México, using scat analysis to determine the diet and prey preferences of pumas and jaguars. Cat species and gender were determined using molecular techniques (rapid classificatory protocol: polymerise chain reaction, RCP–PCR), and prey abundance was estimated from camera trapping. The scats contained remains from 16 wild mammal species, but there was no evidence of livestock or other taxa. The diet breadths of jaguar (0.32) and puma (0.29) indicated a high degree of prey specialization, which combined with their dietary overlap (Pianka index 0.77) suggested competition between them. However, both felids showed a preference for red brocket deer Mazama temama, and frequently consumed collared peccaries Pecari tajacu. The importance of such large ungulates in the felids' diets is similar to the expected patterns of wild meat consumption in rural areas of the Northern Yucatan Peninsula. Therefore, future conservation management plan initiatives should involve local rural communities in the management of sustainable hunting, considering these ungulates are also the felid prey species, El estudio se realizó durante dos años en el noroeste de Quintana Roo, en México y se utilizó el análisis de excrementos para determinar la dieta y las preferencias de presas del puma y del jaguar. Se utilizaron técnicas moleculares para identificar la especie de félido y el sexo (protocolo de clasificación rápida: reacción en cadena de la polimerasa, RCP–PCR), y se estimó la abundancia de presas mediante el método de trampeo fotográfico. Los excrementos contenían restos de 16 especies de mamíferos salvajes, pero no se encontraron restos de ganado ni de otros taxones. La amplitud de la dieta del jaguar (0,32) y del puma (0,29) indica que son especies con un alto grado de especialización, lo cual, junto con el traslape de las dietas (índice de Pianka = 0,77) sugiere que ambos félidos compiten entre sí. Asimismo, ambos mostraron preferencia por el venado temazate, Mazama temama, y frecuentemente consumieron pecarí de collar, Pecari tajacu. La importancia de la presencia de este tipo de ungulados en la dieta de los félidos se corresponde con la pauta esperada de consumo de carne de caza en las zonas rurales del norte de la península de Yucatán. Por lo tanto, las futuras iniciativas encaminadas a planificar la conservación de ambos félidos deberían hacer partícipes a las comunidades rurales en la gestión de la cacería sustentable, considerando que estos ungulados también son presas de los félidos

Thirty-six goats: 15 Alpine (AG), 13 Saanen (SG) and 8 Anglo-Nubian (ANG) were used to evaluate dry matter intake (DMI), body weight (BW) changes and milk production to validate Wood's model in lactation curves. The kids pre-weaning weight, weaning weight (WW) and daily weight gain (DWG) were determined. Milk production was measured daily for a period of 90 d. The DWG was quantified daily, while BW was recorded weekly. Performance of 48 kids (20 AG, 15 SG and 13 ANG), aged 15 d were evaluated. Wood's model was utilised to describe goat's lactation curve in the different studied goat breeds. Milk production was differed between breeds and according to the number of kids suckled (P < 0.05). Both of DMI and BW showed a linear increase (P < 0.05) during the studied period. Both of WW and DWG were unaffected by type of kidding and breed and were higher in males than in females. It is suggested that equation of Wood's model is adequate to describe the lactation curve in studied goat breeds. The ANG and AG breed...

An experiment was conducted to evaluate whether supplementation with a probiotic could enhance digestion and reduce mortality in the volcano rabbit in captivity. Two enclosures at Chapultepec Zoo, Mexico (114 individuals) were used in a cross-over design (two periods of 60 days) with the following treatments: control group and supplementation with Saccharomyces cerevisiae (2×108 CFU/exhibit/day). Supplementation with the probiotic negatively affected (P

The main objective of this study was to determine differences in sperm recovered from the three segments of the epididymis, i.e., head, corpus and cauda, using routine measurements of sperm quality and DNA fragmentation assessment. There was a larger sperm concentration (P < 0.05) in the head (3.34 × 106 sperm/mL) compared with the corpus and cauda. The percentage of normal morphology was higher in the cauda but had lower motility (P < 0.05). The DNA fragmentation index was higher for sperm obtained from the head and body of the epididymis (P < 0.01) compared with the cauda. The DNA fragmentation index values were 12% higher (P < 0.01) using Wright stain compared with DAPI stain in sperm from the head and corpus of the epididymis, but similar in the cauda. Spermatobioscopy parameters match the maturation changes that occur in the epididymal tract with higher quality sperm being from the cauda, but with a lower concentration compared to sperm found in the head.

The objective of the study reported in this Research Communication was to evaluate graded levels of ruminally protected methionine (RPM) in dairy goat rations on milk production and live weight changes during 155 d of lactation. Twenty-five primiparous dairy goats (crosses of Toggenburg, French Alpine and Saanen; 45·4 ± 1·0 kg BW) were fed a basal diet (10·10% CP, 6·13 DP and 2·34 Mcal/kg ME) of corn silage, oat hay, alfalfa hay and concentrate (80% forage, 20% concentrate). After kidding, the treatments, which consisted of four oral doses of ruminally protected methionine (RPM) at 0, 1, 2 and 3 g/d, were randomly assigned to the goats. The experiment was conducted for 110 d with measurements of milk production and composition, body weight and dry matter intake. No treatment effects were detected in milk production and composition. However, goats with RPM showed a positive live weight changes during lactation which were improved as dose was increased (linear P < 0·01) whereas goats without RPM showed weight loss during the experiment.

The effects of two sources of slow-release urea (SRU) with a source of soluble carbohydrates on ruminal fermentation in lambs fed with a low-quality forage hay were evaluated. Optigen is a commercial source of slow-release urea, whereas Surelease is an ethyl cellulose-coated urea prepared in the Laboratorio de Farmacotecnia at the Metropolitan Autonomous University. Five Pelibuey lambs cannulated in the rumen and duodenum (24.8 ± 0.4 kg BW) were used in a Latin Square design. Lambs were fed a basal diet that consisted of Brachiaria brizantha hay and concentrate (ratio 67:33) with the following treatments: (1) feed-grade urea; (2) Surelease-coated urea (SRU-S); (3) SRU-S + molasses; (4) SRU Optigen (OPT); and (5) OPT + molasses. All sources of urea were dosed daily intra-ruminally (0.6 g/kg/BW), and molasses was fed at 1.2 g/kg BW. Compared to feed-grade urea, both sources of SRU decreased ruminal pH between 3 and 6 h after dosing (P

Jaguar and puma faeces (N=30) were collected in an area of 75 km2 in the tropical forest of Tamasopo in San Luis Potosi. A dot-blot assay was developed with DNA from scats in order to differentiate between jaguar and puma. This assay employed a probe recognising cytochrome b of puma. A total of 14 prey species were found, of which 7 were used by both felids. Jaguar and puma diets in this study showed an overlap of 93.38% where collared peccary was the main prey consumed by both felids (jaguar 39.64% and puma 45.76%). White-tailed deer was also present in the diets of both felids, with a similar biomass consumed (jaguar 7.64% and puma 5.88%). Brocket deer and domestic goat appeared only in the puma's diet. With the exception of some remains from a lizard in the jaguar's diet, the rest of the prey species were comprised of medium-sized prey (1–15 kg), with the common opossum and raccoon found for both felids. A method is presented to estimate the number of individuals consumed based on energy requirements. ...

The objective of the study was to evaluate the effect of different levels of Muhlenbergia macroura on feed intake, nutrient digestibility and daily weight changes in volcano rabbits. Thirty-nine-month-old mixed sex rabbits (n=32) were randomly allocated to four dietary levels of M. macroura, i.e. 0, 10, 20 and 30%. Following 14 days of adaptation, daily feed intake (DFI) and daily weight gain (DWG) were recorded and faeces collected during a one-day digestibility trial. Digestibility was estimated with lignin as an internal marker from the feed/faeces ratio. There was no effect (P>0.05) of treatment on DFI. As a daily average, rabbits consumed 26.2 g (SEM 0.20). There were linear (P

In order to evaluate the effect of ruminal undegradable protein (RUP) supplementation on the productive and reproductive performance of double purpose cows, 20 cows (F1 Holstein×Brahman) at 4 days postpartum (body weight 420±24 kg) were divided in two groups (n=20) to receive 2 kg/animal/day of 30% RUP or 45% RUP supplement for 100 days. Cows were weighed, the body condition score (BCS) was recorded weekly and milk production and composition was evaluated twice a week. Faeces, concentrate and pasture samples were collected to estimate forage intake and digestibility. Assessments of oestrous behaviour were performed by visual observation from Day 14 until Day 105 postpartum and blood samples were collected twice a week to measure progesterone. The results show that the use of 45% RUP did not improve intake, digestibility, milk production and composition, body weight or BCS (P > 0.05), but tended to reduce (P = 0.15) the number of days to first normal luteal activity and increased (P=0.14) the number of ani...

8 páginas, 4 tablas, In a randomized block design experiment, the effect of fecal inocula from horses supplemented with live yeast (Saccharomyces cerevisiae) in diets containing 50% oat straw on in vitro total gas (gas production [GP]), methane (CH4), and carbon dioxide (CO2) productions as indicators of hindgut activity was assessed. Three commercial products of S. cerevisiae were tested (1) Biocell F53 (YST53), (2) Procreatin 7 (YST07), and (3) Biosaf SC47 (YST047). For the incubations, each product was added at 0 (control without yeast addition), 2, or 4 mg/g dry matter (DM). Fecal inocula for incubations with each treatment was obtained from Quarter Horse mares fed the same yeast additives for 15 days, resulting in four different fecal inocula (FI53, FI07, FI47, and FI00). The fecal content mixed with the culture media were used to inoculate three identical runs of incubation in bottles containing 1-g DM of substrate (a mixture of concentrate and oat straw [1: 1 DM]). The GP, CH4, and CO2 productions were measured at 2, 4, 6, 8, 10, 12, 24, and 48 hours post-incubation. Addition of additives YST53 and YST07 at 2 mg/g DM resulted in higher asymptotic GP (linear effect, P = .021) and GP during the first 12 hours of incubation (linear effect, P < .05) compared with control without yeast addition, with the highest value being for the dose 2 mg/g DM with the fecal inoculum FI53. The additive YST47 at all doses with fecal inoculum FI47 had lower GP (linear effect, P < .05) at different incubation hours compared with control. The additive YST53 increased GP, CH4, and fermentation kinetics at the dose 2 mg/g DM with decreasing CH4 production by 78% at 4 mg/g DM at 24 hours of incubation. Addition of YST53 at 2 and 4 mg/g DM with fecal inoculum FI53 enhanced fermentation kinetics (P < .05) compared with control and other additives at different doses. It can be concluded that the yeast additive Biocell F53 was the most effective at doses of 2 and 4 mg/g DM compared with other Saccharomyces strains to attain a more favorable hindgut fermentation to digest fibrous roughages by horses. (C) 2016 Elsevier Inc. All rights reserved., Authors thank Universidad Autónoma del Estado de México for financial support of the project #3706/2014 CID. Kholif A.E. thanks the National Council for Science and Technology (CONACyT, Mexico) and The World Academy of Sciences (TWAS, Italy) for his postdoctoral fellowship at the Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma del Estado de México, México.

The objective of this experiment was to evaluate the effect of calcium propionate and grain level on performance and ruminal variables in 32 finishing Criollo lambs (28.14 ± 2.34 kg initial BW) over 42 days. A completely randomized design was used with a factorial arrangement of treatments with either 550 or 650 g grain and 0 or 10 g calcium propionate per kg diet. All diets contained corn grain 200 and molasses 100 g/kg diet. Sorghum grain levels were 350 or 450 g/kg diet, replacing corn stover. No differences were observed in intake, gain or feed conversion among treatments. Rib eye area increased with 650 g/kg grain (P

Supplements with corn grain, molasses cane, and different nitrogen sources were evaluated in 16 growing Hosltein heifers [227 ± 33 kg body weight (BW)] grazing kikuyu (Pennisetum clandestinum) pasture in a 10-ha sward (rotational grazing with electric fences) during 90 days in the summer season. The nitrogen sources were urea (U); urea and blood meal (U + BM); and urea, blood meal, and rumen-protected methionine (U + BM + RPM). Heifers were randomly assigned to four experimental supplements defined as follows: control (no supplementation), U, U + BM, and U + BM + RPM. Two kilograms (as fed) of supplement was offered daily. The final BW of heifers fed U + BM + RPM was higher (P < 0.05) than heifers not supplemented. The total and average daily weight gain of heifers supplemented with U + BM + RPM were higher than heifers not supplemented or supplemented with U and U + BM (P < 0.05). The average daily gain of heifers supplemented with U and U + BM were higher than heifers not supplemented (P < 0.05). Grass intake was not affected by supplementation, but total dry matter intake was increased by supplements with U, U + BM, and U + BM + RPM (P < 0.05). Feed conversion was improved by U + BM + RPM (P < 0.05). Total tract digestion was not affected by supplements. Blood urea nitrogen concentrations of heifers supplemented with U, U + BM, and U + BM + RPM were higher than heifers not supplemented (P < 0.05). It is concluded that supplements with U + BM + RPM improved growth performance and feed conversion in heifers grazing kikuyu pasture.

A factorial experimental design (3 × 2 × 3) was used to evaluate the effect of season of harvest and type of ruminal inoculums on in vitro ruminal fermentation kinetics and energy utilization of three browse tree foliages ( Lysiloma acapulcencis , Quercus laeta and Pithecellobium dulce ). Browse species were harvested during the dry season (DS) and rainy season (RS) and incubated with three different ruminal inoculums: cow, goats previously adapted (AG) or not adapted (UG) to browse species fed in their daily diet. Chemical composition, total condensed tannin (TCT), free-condensed tannin (free-CT), protein-bound condensed tannin (PCT), fiber-bound condensed tannin (FCT) as well as in vitro assaying of ruminal gas production kinetics was determined, while the short chain fatty acids (SCFA) and metabolizable energy (ME) were estimated. Crude protein (CP) was considerably higher (season × browse; P P. dulce had the lowest neutral detergent fiber (NDFom) and acid detergent fiber (ADFom) in both seasons, while L. acapulcencis had the highest values and Q. laeta values were intermediate, with an overall increase in fiber fractions in DS browse foliages (season × browse; P Q. laeta and P. dulce during the RS than in DS, lower (P L. acapulcencis and Q. Laeta than in P. dulce , during both seasons. in vitro gas production parameters was increased (P i.e ., P. dulce and Q. laeta ); consequently, browses energy utilization ( i.e ., SCFA and ME) and organic matter degradability (OMD) as well as fermentation efficiency ( i.e ., partition factor; PF) were improved (P P. dulce had the highest (P L. acapulcencis . Ruminal fluid of AD and UG had higher (P versus in RS and the browse fermentation and utilization were highest (P P. dulce and Q. laeta with low and medium tannins contents and high CP concentration in cows and goats during the DS. Goats previously fed browse species in diets had a better ability to degrade and ferment the browse species than other animals.

Lee-Rangel, H.A., Pinos-Rodriguez, J.M., Mendoza, G.D., Gonzalez, S.S., Monies, M.A., Trejo, A.S. and Jasso-Pineda, Y. 2010. Effect of a ruminal buffer and exogenous amylolytic enzymes on growth and digestion in lambs fed high concentrate diets. J. Appl. Anim. Res., 37: 117–120. To evaluate a ruminal buffer and exogenous amylolytic enzymes from Bacillus licheniformis and Aspergillus niger in high concentrate diet, lambs were fed on diet with no additives, or the same diet supplemented with enzymes (0.26% of diet as DM), buffer (1% of diet as DM) or enzymes + buffer in a growth assay. The supplemented diets did not affect intake, BW changes, feed conversion, rumen digestibility and total tract digestion of DM, organic matter (OM) and starch. Ruminal pH values, ammonia N, lactic acid concentrations and molar proportion of acetate and propionate were similar among treatments. Ruminal molar proportion of butyrate of lambs fed enzymes + buffer was lower than those fed control or buffer diets. Thus exo...

Browse foliages from Lysiloma acapulcencis, Quercus laeta and Pithecellobium dulce, native to the subtropical region of southern Mexico, were harvested during the dry season (DS) and rainy season (RS) to determine in situ degradability using ruminal inoculum from fistulated cows as well as goats previously adapted (AG) or not adapted (UG) to browse species fed in their daily diet. Browse leaf samples were incubated in the rumen of each group for 48 h. The crude protein (CP) content of browse was considerably higher in RS (P

Twelve lactating Saanen goats were fed with a total mixed ration (forage:concentrate 67:33) and directly supplemented (administered orally) with 0, 2.5 and 5.0g/head/day of rumen-protected methionine (RPM) for 30d. Body weight was not affected by RPM. There were quadratic (P

Worldwide big cats are at risk of extinction, and anthropogenic factors and natural habitat disturbances represent the biggest threats for their survival. It is essential to know the natural resources use by these predators and the way these big felids can adapt to changes. It is unknown how the puma (Puma concolor) selects and uses resources, what environmental factors determine its presence and how this species is affected by natural disturbances in Mexican tropical forests. This study was performed in the Eden ecological reserve and surroundings, in the North of Quintana Roo, Mexico, an area dominated by tropical semideciduous (medium forest) and secondary forest (acahual). Camera samplings were carried out during 2008, and from 2010 to 2012. Habitat variables, activity patterns and species associations were also spatially and temporally analyzed using achi-squared test and overlapping coefficients. General Linear Models (GLM) were used in order to determine which variables influence the presence of cougars in the study area. Cougars used vegetation and paths in different proportions as the availability of these resources. The years with more changes (P < 0.05) were 2008 and 2011. This predator was active throughout the day, but changed its activity patterns over the years. The cougar was spatio-temporally associated with six mammals and two big terrestrial birds: Pecari tajacu (∆ = 0.52), Meleagris ocellata (∆ = 0.55), Crax rubra (∆ = 0.58), Didelphis sp. (∆ = 0.64), Mazama temama (∆ = 0.66), Leopardus pardalis (∆ = 0.68), Dasypus novemcinctus (∆ = 0.73) and Panthera onca (∆ = 0.87). After testing 90 GLM models, the model with a lower AIC value described the activity patterns of prey and co-predators. The vegetation and water in the reserve were important variables for the cougar. However the variables that determined and modified the presence of the species were activity patterns of co-predators and the potential preys. The factors that negatively affected the presence of the species were fire, human presence, and habitat displacement to less favorable habitats to avoid jaguar. Rev. Biol. Trop. 66(1): 78-90. Epub 2018 March 01. Resumen Los grandes felinos a nivel mundial se encuentran en peligro de extinción. Los factores antropogénicos y las alteraciones naturales representan una gran presión para su sobrevivencia. Es esencial conocer el efecto de estos sobre los depredadores y cómo los felinos se adaptan y usan los recursos naturales. Se desconoce el modo en que el puma (Puma concolor) selecciona y utiliza recursos, cuáles son los factores ambientales que determinan su presencia y cómo esta especie se ve afectada por alteraciones naturales en los bosques tropicales mexicanos. Este estudio se realizó en la reserva ecológica de El Edén y sus alrededores en el norte de Quintana Roo, México, área dominada por selva tropical semidecidua (selva mediana) y bosque secundario (acahual). Se realizaron muestreos con cámaras durante 2008 y 2010-2012. Las variables de hábitat, patrones de actividad y asociaciones de especies también se analizaron espacial y temporalmente mediante una prueba de chi-cuadrado y coeficientes de traslape. Se utilizaron modelos GLM para determinar qué variables influyen en la presencia de pumas en el área de estudio. El puma utiliza la vegetación y caminos en diferente proporción a la de su disponibilidad. Los años con más cambios (P

In order to evaluate the effect of protein supplementation on the productive and reproductive performance of heifers, 45 Bos indicus x Bos taurus heifers, 673 +/- 146 days of age and weighing about 340 kg, were divided into two groups. The control group (n = 23) continued without supplementation, but the supplemented group (SG; n = 22) received concentrate at a rate of 1% BW kg per day. Animals were adapted to the concentrate over a 15-day period and then supplemented for 30 days, after which estrus was synchronized using a progesterone implant. Back fat thickness (BFT) was assessed by ultrasound. The SG had better average daily weight gain than the nonsupplemented group (0.63 +/- 0.16 vs. 0.51 +/- 0.13 kg/day, P0.05) and tended to show a better percentage ovulation (P0.10, 77% vs. 57%, respectively). However, this tendency was not reflected in the final pregnancy rates. No differences were observed between groups in dry matter intake and body condition scores. SG with a high BFT (0.70 cm) showed a better ovulation percentage than those with low BFT (0.69 cm; P0.01). Additionally, the pregnancy rate of supplemented heifers with high BFT tended to be better than heifers with low BFT in this same group (67% vs. 30%, respectively, P0.10). It is concluded that protein supplementation improved reproductive performance and that ultrasonography to measure BFT may be used to estimate reproductive performance.

Clemente F., Holechek, J. L., Valdez, R., Mendoza, G.D. 2009. Influence of range condition on pronghorn (Antilocapra americana) and cattle diets in southern New Mexico. J. Appl. Anim. Res., 36: 13–16. A study was conducted to evaluate the influence of good (GC) and fair (FC) range condition classes on pronghorn and cattle diets. There was a higher preference for the GC (84%) than for the FC (16%) area (P

The objectives of this study were to evaluate the chemical composition, intake, N balance, total tract digestion and ruminal disappearance of dry matter (DM) and neutral detergent fiber (NDF) of Agave salmiana harvested when young or mature and fed either fresh or as silage to lambs. The experimental design was a 4 × 4 Latin square with a factorial (2 × 2) arrangement of treatments: (a) process = fresh or silage; (b) agave age = young (12 years) or mature (16 years and sterilized). Young agave had a higher organic matter (OM) and lower crude protein (CP) and saponin concentrations than mature. Ensiling decreased soluble carbohydrates (SC), saponin concentrations, and pH. Dry matter and OM intakes of agave fresh were lower than others. Saponin intake was lower with agave silage than fresh. Total tract digestion was not altered by treatments. The highest nitrogen retention value was found in lambs fed mature agave as silage. Both ruminal disappearance of the insoluble fraction and disappearance rate of DM and NDF for young were higher than for mature agave. Ruminal molar proportion of propionate was higher and acetate:propionate ratio was lower in lambs fed agave silage than fresh. Lambs fed young agave had lower ciliate protozoa numbers than those fed mature agave. Ensiling agave increased NDF disappearance, ruminal fermentation and N balance in lambs.

This experiment was designed to study effects of exogenous fibrolytic enzymes on digestibility and ruminal fermentation of total mixed rations (TMR) with different forage:concentrate (F:C) ratios. The experimental design was a 6×6 Latin square with six ruminally cannulated Ramboulliet lambs (58 ± 7.4 kg body weight) used in a 3×2 factorial arrangement of treatments using three forage:concentrate (F:C) ratios (400:600, 500:500, 600:400 kg/kg) and two (0 or 2 g) levels of fibrolytic enzymes/kg TMR dry matter (DM). Exogenous fibrolytic enzymes increased the soluble fraction of DM (P

To evaluate supplementation with the yeast products Saccharomyces cerevisiae CNCM I-1077 (SC) and Saccharomyces boulardii CNCM I-1079 (SB) on performance of calves, 24 Holstein calves (12 males, 12 females) were randomly assigned to each of 3 treatments being: C (control treatment), SC (1 g/d); or SB (1 g/d). Calves were fed whole milk (4.5 l/d) and a starter feed ad libitum from 4 d of age until weaning . Female calves were weaned at 60 d of age. Neither yeast affected body weight, body weight gain or feed efficiency, although dry matter intake was higher (P versus control calves. The incidence of diarrhea and pneumonia was similar between treatments. Ruminal ammonia N, propionate and butyrate increased with SC (P

Rojo, R., Mendoza, G.D., Plata, F.X., Lara, A. and Barcena, R. 2007. Comparison of method of application on the effect of amylolytic enzymes on in vitro ruminal starch digestion. J. Appl. Anim. Res., 32: 81–84. An in vitro, experiment was designed to study the efficacy of two amylolytic enzymes on starch digestion of corn applied to grain 24 h before incubation or at the beginning of the fermentation. Both enzymes, amylase from B. licheniformis, and glucoamylase from A. niger, increased starch digestion and there was no effect of the aspersion of the enzyme before the incubation, or the addition of the solution during the fermentation. It is concluded that even when enzymes are soluble proteins, resistance to ruminal degradation is not improved by the contact with the grain before incubation.

We evaluated the nesting by Crocodylus moreletii in Lago de Catemaco, Veracruz, southeastern, Mexico. During the nesting and hatching seasons, we searched for nests along the northern margins of the lake and small associated streams. We investigated egg mortality by weekly monitoring each of the nests found, recording sign of predation (tracks and holes dug into the nest) and the effect of water level fluctuations. We not found differences to nest between inland or flooded zones. However, we found that egg size varied among nests. In nests built inland, predation was the major cause of egg mortality whereas flooding resulted in more deaths of eggs in the flooding zone. Flooding killed 25% of eggs monitored in this study. We suggest that to increase nest success in the Morelet’s crocodile it is necessary to promote conservation of nesting areas around the lake, recently occupied by urban or tourist developments. Resumo Nós avaliamos a nidificação numa população de Crocodylus moreletii no Lago de Catemaco, Veracruz, sudeste, México. Durante as temporadas de nidificação e eclosão buscamos ninhos ao longo das margens situadas ao norte do lago e pequenos riachos associados. Estabelecemos a mortalidade de ovos por semana monitorando cada ninho achado, registrando qualquer sinal de predação (rastros e buracos cavados no ninho) e o efeito das flutuações no nível da agua. Não achamos nenhuma preferência para aninhar na terra ou em áreas inundadas. Por outro lado, achamos que o tamanho de ovo foi significativamente diferente entre os tipos de ninho. Em ninhos construídos na terra, a predação foi a principal causa da mortalidade de ovos enquanto que nas áreas inundadas, inundação foi um fator importante na morte dos ovos. Em comparação com depredação, a ruptura acidental e colonização fúngica, as inundações mataram 25% de ovos monitorados. Nós sugerimos que para aumentar o sucesso de aninhamento do crocodilo do Morelet é preciso promover a conservação das áreas de nidificação ao redor do lago, recentemente ocupadas pelo desenvolvimento urbano ou turístico.

The partial substitution of soybean meal by Gliricidia sepium or Guazuma ulmifolia leaves in the rations of growing lambs was evaluated at an experimental station in the dry tropics of Mexico. Sixteen weaned crossbred male Pelibuey × Blackbelly lambs (initial weight 19 ± 1.66 kg), distributed in a completely randomized design, were assigned to the following protein sources: (a) 100% soybean meal, (b) 50% soybean meal + 50% G. sepium, (c) 50 % soybean meal + 25% G. ulmifolia + 25% G. sepium, and (d) 50% soybean meal + 50% G. ulmifolia in isoproteic rations. The lambs were housed in individual pens and fed ad libitum. Substitution of protein from soybean meal with G. ulmifolia did not affect gain, intake, or feed conversion; however, the inclusion of G. sepium reduced (linear effect, P

Forty multiparous cows (599 kg ± 18 kg BW) were fed with a basal diet (19.6% CP, 35% RUP, and 1.7 Mcal kg − 1 NEl) with alfalfa, corn silage and concentrate (49% forage: 52% concentrate). After calving, cows were randomly assigned to the treatments, which consisted in four levels of ruminally protected methionine (RPM): 0, 8, 16 and 24 g d − 1 of Mepron®M85 (Degussa Co.). Experiment was conducted for 120 days with measurements of milk production, composition, body weight, body condition score and DM intake every 15 days (3 consecutive days) starting on day 5 postpartum. Data were analyzed with the repeated measures model (four treatments in 8 periods through lactation). No treatment effects were detected on DM intake (20.38 ± 2.51 kg d − 1 ), body weight (599.78 ± 19.78 kg), body condition score (2.51 ± 0.19 units) and milk fat. However, milk production and protein yield were increased with addition of RPM ( P − 1 milk require addition of ruminally protected methionine (16 g d −1 ) to improve milk production.

Two industrial exogenous enzymes, alpha-amylase from Bacillus licheniformis and glucoamylase from Aspergillus niger, were evaluated in vivo and in lambs fed 700 g/kg (dry matter (DM)) sorghum grain diets. Six Suffolk lambs (30 ± 2.5 kg body weight (BW)) fitted with ruminal and duodenal cannulas were randomly allotted to two 3 × 3 Latin square experiments, to evaluate effects of alpha-amylase and glucoamylase on intake, digestibility and ruminal fermentation. The same level of protein from the two enzyme sources (0.0, 1.45 or 2.90 g enzyme/kg DM sorghum) was applied to sorghum. The enzymes were sprinkled on the sorghum 24 h before mixing the diet. The highest level of each enzyme was also fed (45 days) to 15 individually housed lambs (Suffolk crossbred, 22.5 ± 1.4 kg BW) in a completely randomized design (i.e., control, alpha-amylase or glucoamylase) to evaluate lamb performance. The highest activity units/mg protein (P

The diets of prairie dog (Cynomys mexicanus) and cattle (Charolais cows) in desert grassland of northern Mexico were examined in 1-year study using microhistological analysis of feces. Cattle utilized more ( P 0.01 ) grasses than prairie dogs (86% vs. 68% across seasons). One key forage species in cattle diets was Bouteloua curtipendula, which was eaten in greater ( P 0.05 ) amounts by cattle than prairie dogs in summer and winter. Bouteloua gracilis, consistently appeared in cattle feces in all seasons. With the exception of spring, this grass was two-fold higher ( P 0.01 ) in cattle than prairie dog diets. Prairie dogs consumed 31% forbs compared to 16% for cattle (data across seasons; P 0.05 ). Due to the low woody plant availability in the pasture, shrub was a negligible dietary constituent of both herbivores. In general, prairie dogs had a greater preference than cattle for forbs. Overall dietary overlap between prairie dog and cattle was 68%, which indicates that large forage competition occurs between prairie dog and cattle in all season. However, the long-term profitability of the ranch where these prairie dogs live, and the steady expansion of prairie dog colonies in this area indicates that controlled livestock grazing can be biologically sustainable, compatible with prairie dogs and economically cost effective.

Diets of prairie dogs, goats, and sheep were examined by microhistological fecal analysis during 4 periods of a year in a desert rangeland in northern Mexico. Prairie dogs selected more grasses (79% across all seasons; P , 0.05) than goats and sheep during most of the year. Total grasses in goat diets were consistent (20%) in all seasons, whereas this forage class was highest during winter (72%) and lowest during summer (62%) in sheep diets. The diet of goats was predominantly shrubs (45%–62%) in all seasons, whereas sheep and prairie dogs ate little browse throughout the study. All 3 species preferred forbs, which contributed about one-third to the composition of the prairie dog (winter), goat (summer), and sheep (spring) diets. Acacia greggii Gray and Opuntia rastrera Weber were the most preferred species by goats, whereas prairie dogs and sheep showed particular preference for Buchloe dactyloides (Nutt.) Engelm. and Bouteloua gracilis (Willd. ex Kunth) Lag. ex Griffiths. During summer and spring, concentration of nitrogen in the feces of sheep was 36% and 17% higher (P , 0.05) than in the feces of goats. There was a high overlap in diets between prairie dog and sheep in all seasons, whereas diets of prairie dogs and goats, and goats and sheep were significantly different from each other in all seasons. These results showed that competition was keen between prairie dogs and sheep for a limited quantity of forage in this arid zone pasture, whereas goats were better able to use common resources with prairie dogs.

Gutierrez, C., Mendoza, G.D., Pinos-Rodriguez, J.M., Ricalde, R., Aranda, E. and Miranda, L.A. 2005. Effect of storage time and processing temperature of grains with added amylolytic enzymes on in situ ruminal starch digestion. J. Appl. Anim. Res., 27: 39 Amylolytic exogenous enzymes may increase ruminal digestion of grains. However, stability of enzymes during feed processing can be a constraint for its utilization. Therefore, the objective of this study was to evaluate the efficacy of B. licheniformis amylase and A. niger glucoamylase, according to time of storage after treatment and duration of exposition at 100 C, using corn and sorghum and its effect on in situ ruminal digestibility (12 h incubation) of dry matter and starch. A generalized randomized complete block design was used in the assays, using the block × treatment interaction as the error term. Ruminal starch digestibility (%) was not affected by either time (1, 4, 7, 15 and 30 days) of aspersion before incubation or by the time (0....

Gutierrez. C., Mendoza, G.D., Ricalde, R., Melgoza, L.M. and Plata, F. 2005. Effect of exogenous amylase or glucoamylase dose on in situ ruminal digestion of corn and sorghum. J. Appl. Anim. Res., 27: 7–10. Several processes have been developed to increase ruminal digestion of grains. Treatment of grains with exogenous amylase from Bacillus licheniformis and with glucoamylase from Aspergillus niger has increased ruminal digestion. An in situ assay was conducted to determine the effects of the dose of exogenous amylolytic enzymes on in situruminal digestibility (12 h incubation) of corn and sorghum. A complete generalized randomized block design was used, with incubations as blocking criteria. In situ dry matter digestion was increased (P

Crosby, M.M., Mendoza, G.D., Barcena, R., Gonzalez, S. and Aranda, E. 2004. Influence of Saccharomyces cerevisiae dose on ruminal fermentation and digestion in sheep fed a corn stover diet. J. Appl. Anim. Res., 25: 9–12. A metabolism trial was conducted to evaluate Saccharomyces cerevisiae dose on ruminal fermentation and digestibility. Fourteen Suffolk ewes (35±4 kg BW) with ruminal and duodenal cannula were assigned to a completely randomized design, where treatments were intraruminal dose of microbial culture of Yea-Sacc1026 (0, 1, 3, 5 and 7g/d). Diet was based on corn stover (66.5%), sorghum gram (23.5%), molasses (10.2%) and urea (1.3%). Ruminal pH, VFA concentration, molar proportion of VFA and ammonia-N were not affected by dose. Protozoa population (5.3, 9.6, 11.4, 8.9, 4.0 organisms x 101) showed a quadratic effect (P

Mendoza, G.D. and Britton, R.A. 2003. Response of intestinal starch digestion to duodenal infusion of casein. J. Appl. Anim. Res., 24: 123–128. To determine the effect of duodenal infusion of intact casein at 0, 20 or 40 g/d level on intestinal starch digestion, fifteen ruminally, duodenally and ileally fistulated sheep were assigned randomly to treatments. Treatments did not affect percent casein digestion in different parts of gastrointestinal tract. Starch digestion in the small intestine, expressed as a percentage of that entering, increased linearly (P

This experiment was conducted to study the effects of fibrolytic enzymes (Fibrozyme) on gain and digestibility of steers grazing stargrass and sugar cane plus urea as a complementary forage in tropical conditions. Twenty crossed (Bos taurus×Bos indicus) steers (270±30 kg BW) were used in a grazing trial (80 days), feeding individually concentrate (1 kg/d, 14% CP) and urea treated sugar cane (USC), in a completely randomized design according to the following treatments: (1) Grazing control (GC); (2) USC-0; (3) USC+15 g d−1 Fibrozyme (USC-15); (4) USC+30 g d−1 Fibrozyme (USC-30). The stocking density was 6 steers ha−1. Forage intake was estimated with makers (chromic oxide and acid insoluble ash). Gain was improved with fibrozyme showing a positive (P

Sixteen growing intact male Criollo sheep, 19.9±2.5 kg initial live weight, were randomly allocated to metabolic cages. Four treatments with four replications were evaluated. The treatments were: T1=100% Kikuyu (Pennisetum clandestinum) grass hay (KGH); T2=25% Buddleia skutchii leaves (BSL)+75% KGH; T3=50% BSL+50% KGH, and T4=75% BSL+25% KGH. The highest (P 0.05) and both were higher in comparison with the rest of the treatments. Digestibilities of dry matter (DM), crude protein (CP), NDF and acid detergent fibre (ADF) were not statistically different (P>0.05) for treatments T1, T2 and T3, and both T1 and T2 were significantly (P 0.05). Nevertheless, there was a clear tendency in reduced DMI, digestibilities and DLWG when replacing KGH with 50 or 75% of BSL. In addition, a basic economic evaluation was carried out. The best net benefit (NB; US $1.01) and direct return rate (DRR; US $0.32) was for T1, but both NB and DRR were reduced for all levels of BSL inclusions.

Defecation rate is important to estimate wildlife populations based on pellet-counts procedures. An experiment utilising volcano rabbit (Romerolagus diazi) was conducted to evaluate the number of pellets produced per rabbit per day and its correlation with weight of the excreta, when they were fed with different levels of Muhlenbergia macroura (0, 10, 20, and 30%). Thirty individuals (538.25±23.47 g BW) were randomly distributed in four diets; the average numbers of faecal pellets dropped per rabbit in 24 h were measured during eight days. A total of 69,955 faecal pellets were collected, with a defecation rate of 253.46±4.07 pellets/rabbit/day and an average weight of 10.39±3.99 g. There was a high correlation between defecation rate and weight (R 2=0.76, p 0.10) in defecation rate by M. macroura levels in the diet. For this reason, this index can be used to estimate R. diazi population in the wildlife.

We determined the response properties of neurons in the primate medial premotor cortex that were classified as sensory or motor during isochronous tapping to a visual or auditory metronome, using different target intervals and three sequential elements in the task. The cell classification was based on a warping transformation, which determined whether the cell activity was statistically aligned to sensory or motor events, finding a large proportion of cells classified as sensory or motor. Two distinctive clusters of sensory cells were observed, i.e. one cell population with short response-onset latencies to the previous stimulus, and another that was probably predicting the occurrence of the next stimuli. These cells were called sensory-driven and stimulus-predicting neurons, respectively. Sensory-driven neurons showed a clear bias towards the visual modality and were more responsive to the first stimulus, with a decrease in activity for the following sequential elements of the metronome. In contrast, stimulus-predicting neurons were bimodal and showed similar response profiles across serial-order elements. Motor cells showed a consecutive activity onset across discrete neural ensembles, generating a rapid succession of activation patterns between the two taps defining a produced interval. The cyclical configuration in activation profiles engaged more motor cells as the serial-order elements progressed across the task, and the rate of cell recruitment over time decreased as a function of the target interval. Our findings support the idea that motor cells were responsible for the rhythmic progression of taps in the task, gaining more importance as the trial advanced, while, simultaneously, the sensory-driven cells lost their functional impact.

The aim of the present study was to evaluate the effects of L-arginine-HCl supplementation on ovulation rate, fertility, prolificacy, and serum VEGF concentrations in ewes with synchronized oestrus. Thirty Suffolk ewes with a mean body weight of 45 ± 3 kg and a mean body condition score (BCS) of 2.4 ± 0.28 were synchronized for estrus presentation with a progestin-containing sponge (20 mg Chronogest® CR) for 9 days plus PGF2-α (Lutalyse; Pfizer, USA) on day 7 after the insertion of the sponge. The ewes were divided into two groups; i.e., a control group (n = 15) that was fed on the native pasture (basal diet) and an L-arginine-HCl group (n = 15) that received 7.8 g of rumen-protected L-arginine-HCl from day 5 of the sponge insertion until day 25 after mating plus the basal diet. The L-arginine-HCl was administered daily via an esophageal probe between days 5 and 9 of the synchronization protocol and every third day subsequently. Blood samples were drawn from the jugular vein every 6 days throughout the entire experimental period. The results revealed that the L-arginine-HCl supplementation increased fertility during the synchronized estrus (P = 0.05). However, no effects were observed on the final BCS (P = 0.78), estrus presentation (P = 0.33), multiple ovulations (P = 0.24), prolificacy (P = 0.63), or serum VEGF concentration. In conclusion, L-arginine-HCl supplementation during the period used in this study increased fertility in sheep with synchronized estrus possibly due to improved embryo-fetal survival during early pregnancy.