Search

The study presents the results of a survey of agricultural enterprises and peasant farms in the Sakhalin Oblast. The authors conducted the visual estimation of the feed consumption and cows’ overall health, revealed the chemical analysis of primary zootechnical parameters of the feed, compared the results with the rates and previous data, and gave recommendations. Moreover, the authors assessed the fodder, feed allowance and compared it with the nutritional rates using the software “Feeding rations” developed by the “Plinor limited liability company”. Furthermore, one can identify that the daily milk yield of Holstein cows doubled in the period 2001–2010, but the feed allowance of the Holstein cows during lactation and dry periods still did not meet nutritional requirements. The low nutritional value of green forage is caused by the small amount of legumes in the herbage. One should prepare winter forage earlier to improve the quality of ration (hay, haylage, silage). Mowing grasses ten days later than the optimal time leads to a protein decrease in forage by 30%–35%. It is crucial to balance the feed allowance with biological and mineral supplements, adding grain mixture or sunflower cake.

• A 5 kg greater live weight at the start of the mating period increased the reproductive rate of Merino ewe lambs mated at 7 to 8 months of age by 20%. • Gaining an extra 100 g/day of live weight during the mating period further increased their reproductive rate by 20%. • Ewe lambs from sires with higher breeding values for fat measured post-weaning achieved a higher reproductive rate. • The effects of managing growth pattern until the end of the mating period and sire genetics on fertility and reproductive rate were additive. • Survival of twin born progeny from ewe lambs was lower than the survival of single born progeny (68 vs 93%; P < 0.001). The reproductive performance of Merino ewe lambs is highly variable and generally poor in comparison to older ewes. In this study, we determined the impacts of growth pattern to the end of the mating period and sire genetics on the reproductive performance of Merino ewe lambs. Five hundred ewe lambs with full pedigree records were managed under commercial conditions from weaning and weighed 43.5 kg at the start of the mating period with an average age of 224 days. The ewe lambs were offered a moderate or high feed allowance to achieve target growth rates of 100 or 200 g/day during a 46-day mating period. They were then recombined and scanned for pregnancy status 60 days after the mating period. At the individual animal level, a 5 kg greater live weight at the start of the mating period increased reproductive rate (foetuses per 100 ewes joined) by about 20% (P < 0.001). Regardless of their live weight at the start of the mating period, gaining an extra 100 g/day of live weight during the mating period further increased their reproductive rate by about 20% (P < 0.001). Ewe lambs from sires with higher Australian Sheep Breeding Values for fat measured post-weaning achieved a higher fertility (P < 0.05) and reproductive rate (P < 0.01) regardless of feed allowance treatment. The effects of sire fatness was significant even when the sire breeding values for live weight measured post-weaning were included in the model. The effects of managing growth pattern and sire genetics were additive, so improving the reproductive performance of Merino ewe lambs mated at 7 to 8 months of age requires improving their feed allowance and rate of live weight gain until the end of the mating period and using sires with higher breeding values for fatness. [ABSTRACT FROM AUTHOR]

Variability in bodyweight (BW) among pigs complicates the management of feeding strategies and slaughter. Including variability among individuals in modelling approaches can help to design feeding strategies to control performance level, but also its variability. The InraPorc model was used to perform simulations on 10 batches of 84 crossbred pigs each to characterise the effect of feeding strategies differing in amino acid supply or feed allowance on the mean and variation in growth rate. Results suggested that a feed restriction reduces the coefficient of variation of BW at first departure for slaughter (BW1) by 34%. Growth performance obtained from an in silico simulation using ad libitum and restricted feeding plans was compared with results obtained in an in vivo experiment on a batch of 168 pigs. Pigs were offered feed ad libitum or were restricted (increase in feed allowance by 27 g/day up to a maximum of 2.4 and 2.7 kg/day for gilts and barrows, respectively). A two-phase feeding strategy was applied, with 0.9 and 0.7 g of digestible lysine per MJ of net energy (NE) in diets provided before or after 65 kg BW, respectively. Actual growth was similar to that obtained by simulation. Coefficient of variation of BW1 was similar in vivo and in silico for the ad libitum feeding strategy but was underestimated by 1 percentage point in silico for the restriction strategy. This study confirms the relevance of using simulations performed to predict the level and variability in performance of group housed pigs. Variability of bodyweight among pigs complicates management decisions related to feeding and slaughter; growth models that account for variability can be used to test and to propose feeding strategies to control this variability. This study demonstrates this concept and confirms its applicability in an in vivo experiment. Decision support tools based on such a modelling approach can be developed to propose feeding strategies allowing reaching target levels of performance in many fields (growth rate, economy and environmental impact). [ABSTRACT FROM AUTHOR]

An experiment was conducted in New Zealand to assess the effect of creep grazing of lambs on their liveweight and resistance to endoparasites. Comparisons included creep versus non-creep grazing at two herbage allowances and regular anthelmintic drenching. Treatments commenced with 6-week-old twin reared lambs, and ceased when they were weaned at 13 weeks, with the exception of the drench treatment which continued post-weaning. Pastures used contained sheep endoparasites. At 8 weeks post-weaning one lamb from each twin set was slaughtered, remaining lambs were then drenched, and 8 and 9 days later were orally dosed with 180 Trichostrongylus colubriformis L3/kg liveweight each day (averaging 12 650/lamb). Three weeks later these lambs were also slaughtered. Measurements included liveweight, faecal worm egg count (FEC) and adult endoparasite numbers. Neither herbage allowance nor creep grazing affected FEC or adult endoparasite numbers. Fortnightly drenching of creep grazed lambs on the high allowance had no effect on weaning liveweight, but it improved liveweights post-weaning. Neither creep grazing, pre-weaning herbage allowance, nor drenching, affected lamb resistance to endoparasites. Creep grazing and the higher allowance both increased weaning liveweights. The response to creep grazing was highest at the lower allowance, increasing weaning liveweights by 4 kg. Pre-weaning treatment had no effect on post-weaning growth rate. [ABSTRACT FROM AUTHOR]

The aim of this study was to compare and relate plasma hormone levels of luteinizing hormone (LH), follicle-stimulating hormone (FSH), progesterone (P4), estradiol (E2), and the in vitro P4 production capacity of the largest yellow (F1) follicle granulosa cells with the laying performance of 2 genotypes (a standard S line and a dwarf cross-experimental E line) maintained under ad libitum (SA, EA) or restricted (SR, ER) feeding regimens. Age-related hormone changes were determined from 4 to 50 wk, hormone changes during the ovulatory cycle were determined during lay, and changes in follicle granulosa cell P4-producing capacity in response to LH with or without growth factors were measured in vitro at different ages. The mean laying rate was similar for SR, EA, and ER but were lower for the SA. Plasma LH and FSH concentrations increased with age in all groups and peaked at puberty. Restricted feeding delayed puberty in both genotypes. Concentrations of E2 and P4 increased after puberty in all groups but delayed in restricted hens. Plasma levels of LH, FSH, P4, and E2 before and after puberty were not correlated with egg-laying performance, but peak E2 levels were. Luteinizing hormone and P4 concentrations during the ovulatory cycle showed differences that may be associated with the different laying performances of the 2 genotypes under ad libitum and restricted feeding. The increase in plasma LH concentration (from basal) during the preovulatory surge was higher in the SR than in the SA but was similar for EA, ER, and SA. The increase in P4 was also higher in SR than in the SA with no difference between EA and ER. In vitro P4 production by granulosa cells in response to LH with insulin-like growth factors, and bone morphogenetic protein-7 was different among the SA, SR, EA, and ER; the EA, SR, and ER had greater responses, and the SA had less response. The presence of insulin-like growth factors and bone morphogenetic protein-7 enhanced LH effects depending on the feeding regimen and age of hen. This finding suggests that differences in laying performances among genotypes fed at different nutritional levels may be partly due to differences in processes associated with follicular maturation modulated by gonadotropins and growth factors. It is concluded that the age at puberty is determined mainly by feed allowance, irrespective of genotype, and that differences in laying performance may be due to a combination of factors that include changes in the levels of gonadotropins or ovarian hormones and growth factors, BW, and the condition of the different genotypes under different feeding allowances. [ABSTRACT FROM AUTHOR]

Ad libitum feeding reduces livability and reproductive fitness in broiler breeder hens. Two geno-types, a standard (S) and an experimental dwarf broiler breeder (E), were fed ad libitum (SA and EA, respectively), restricted at 55% of ad libitum feed intake (intermediate restriction) from 6 to 15 wk of age (SI and El, respectively), or restricted (SR and ER, respectively) to match a standard growth curve with a diluted mash feed (2,400 kcal/kg). The experiment was repeated at 2 locations (experiment 1 = 672 hens in pens from 0 to 40 wk; experiment 2 = 420 hens in pens and cages from 0 to 53 wk). Feed restriction reduced adult BW by 20% compared with ad libitum feeding, delayed sexual maturity by 2 to 4 wk, and improved livability. Hens fed the intermediate diet immediately compensated after 15 wk of age to reach BW, sexual maturity, and livability close to those of ad libitum-fed hens. The E genotype exhibited better tolerance to ad libitum feeding than the S genotype in all measured aspects. Average laying rate during the first 24 wk of lay was 66.4, 77.4, 69.9, 47.2, 57.9, and 72.4% for EA, El, ER, SA, SI, and SR respectively in experiment 2. Egg abnormalities (double yolk, shell problems) decreased after the peak of lay but remained consistently higher for S compared with E, and for ad libitum and intermediate diets compared with the restricted diet. Yolk deposition rate was measured by a double dye technique. Duration of yolk rapid growth was 8.8 d in E and 9.3 d in S hens (P < 0.001), but this difference did not explain the observed variations in laying rate. The potential to increase feed allowances even with a diluted diet in broiler breeder hens requires adapted genotypes. [ABSTRACT FROM AUTHOR]

The influence of differentiated extra maternal feed allowance during early gestation on maternal performance and postnatal development of the progeny from gilts and sows was investigated. Four different feed allowances of the same diet (Control [C], +35% [T35], +70% [T70], +100% [T100]) were assigned to 20 crossbred gilts (Swedish Landrace×Swedish Yorkshire), which continued as sows with the same feed allowance the following parity. The progeny was uniformly raised and slaughtered at a live weight of 110 kg. Additional maternal feed allowance resulted in significantly more weaned piglets per sow but not per gilt. Piglet numbers did not increase from T35 to T70/T100. Piglet birth weight did not increase due to maternal feeding. The intra-litter variation in piglet birth weights was similar between the treatments. Independent of the additional feed allowance, all gilts and sows had similar weights after weaning and had good body condition. The growth rate of progeny from sows was negatively related to maternal feed supply; for progeny from gilts, no clear trend of nutritional influence could be observed. Carcass and technological meat quality was not affected by maternal feeding treatment. Birth weight positively affected later growth performance (daily weight gain), carcass quality (lean meat content, back fat, proportion of muscles in ham/loin), whereas technological meat quality was unaffected. [ABSTRACT FROM AUTHOR]

A study was conducted to determine if channel catfish yield in ponds can be maintained with reduced feed allowance, while increasing protein concentration in the diet. Channel catfish (Ictalurus punctatus) fingerlings (16.7 g average wt.) were stocked in twenty 400-m2 earthen ponds at a density of 13,750 fish/ha. Diets were prepared to contain three percentages of protein (P) at constant and variable digestible energy (DE) concentrations. One group of diets contained 28%, 32% or 36% protein and a constant level of DE, 3.08 kcal/g of diet. Another group of diets contained the same series of protein percentages and variable levels of DE, 2.70, 3.08 and 3.41 kcal/g, so that DE/P ratio was constant at 9.6 kcal/g. The diet containing 28% protein and 3.08 kcal DE/g diet was the control which was fed at satiation rate. The daily allowance of all the other diets was based upon the amount of protein consumed by the control fish; all treatments received the same daily protein allowance. Therefore, fish fed with the 32% protein diet received 12.5% less feed than the control and those fed with 36% protein diet received 22.2% less than the control. The feeding trial lasted 19 weeks, from June 1 to October 5. When DE level of the diets was constant at 3.08 kcal/g, weight gain of fish was not different (P>0.05) from the 28% protein treatment (satiation fed) and the 32% protein treatment (87.5% of satiation), but weight gain was lower (P<0.05) in the 36% protein treatment (77.8% of satiation). When the DE level of the diets changed in proportion to the protein content to provide a constant DE/P ratio, weight gain for the 32% protein treatment (87.5% of satiation) was higher (P<0.05) than that of the 36% protein treatment (77.8% of satiation), but not different (P>0.05) from the 28% protein treatment (100% of satiation). Feed efficiency ratio (FER) improved (P<0.05) as protein level increased from 28% to 32%, with a 12.5% decrease in feed allowance, at constant and variable DE levels; however, FER did not improve (P>0.05) as protein level increased from 28% to 36%, with a 22.2% reduction in feed allowance. There was no difference (P>0.05) in total ammonia nitrogen (TAN), nitrite nitrogen, biochemical oxygen demand (BOD5), chlorophyll a or soluble phosphorus in pond water among treatments; however, TAN, nitrite nitrogen, and BOD5 changed (P<0.05) over time as feed allowance increased. Among the treatments evaluated, commercial fish farmers may find the 32% protein, 3.08 kcal/g DE and 87.5% satiation regimen, the most practical since they can feed to less than satiation, obtain a better FER, and optimize production. [Copyright &y& Elsevier]

The objective was to determine the influence of feed intake (FI) and fiber source on the apparent total tract digestibility (ATTD) of gross energy (GE) and nutrients in pigs. Twelve barrows with an initial body weight (BW) of 34.0 ± 2.6 kg were allotted to a replicated 6 × 4 Latin square design with 6 treatments and 4 periods. The 6 treatments were consisted of a 2 × 3 factorial arrangement with 2 amounts of FI (9.0 and 4.5% × BW0.75) and 3 dietary fiber sources. Three diets were 1) a corn-soybean meal-based basal diet (BD), 2) a diet replacing 30% of corn and soybean meal in BD with sugar beet pulp (SBP) as a source of soluble dietary fiber (SDF), and 3) a diet replacing 15% of corn and soybean meal in BD with corn cobs as a source of insoluble dietary fiber (IDF) to obtain a similar IDF concentration as in the SBP diet. Following a 6-d adaptation, feces were collected for 5 d. The ATTD of GE, dry matter (DM), organic matter (OM), neutral detergent fiber (NDF), and acid detergent fiber (ADF) in diets was greater (P < 0.05) for pigs fed at 4.5% of BW0.75 compared with those fed at 9.0% of BW0.75. The ATTD of GE, DM, OM, NDF, and ADF in SBP diet was greater (P < 0.01) than that in corn cob diet. However, there was no interaction between FI and fiber source on energy and nutrient digestibility. The ATTD of GE, DM, OM, protein, NDF, and ADF in SBP was greater (P < 0.01) than that in corn cobs. In conclusion, energy and nutrient digestibility values were increased by reduced feed intake and were greater in sugar beet pulp than in corn cobs without interaction between feed intake and fiber source. [ABSTRACT FROM AUTHOR]