Kg For Lambs Research Articles

ВЛИЯНИЕ МОЛОЧНОСТИ И ДОЕНИЯ МАТОК НА РОСТ И ПРОДУКТИВНОСТЬ ЯГНЯТ

A shortening of the milking period has a negative effect on lambs, and this effect is more pronounced the earlier the beating is carried out and milking begins, but the growth of young animals is highly dependent on the level of non-dairy nutrition and rearing technology. In this regard, the study of the influence of milking on the quality and productivity of the offspring was carried out taking into account the characteristics of feeding and keeping lambs. The experiment was carried out in 2023 in the foothill zone of the Republic of North Ossetia-Alania on sheep of the Tushino breed. All experimental lambs were divided into two groups: a control group, raised in the usual manner, and an experimental group, whose queens were not milked. All lambs had coarse wool, were kept in the same conditions and were allowed access to the uterus 2 times a day - in the morning and in the evening, but the rest of the time they were kept separately. Milking of sheep on the farm began in early June, that is, when the lambs reached 2.5 months of age. Lambs of both groups were completely weaned at 5 months of age. It was found that the lambs of the experimental group, whose uterus were not milked, grew better and had a greater body weight at the time of lambing than the control group. The difference in body weight was 1.92 kg for rams and 2.42 kg for lambs, in favor of the experimental group. After the start of milking of the queens of the control group, the picture changes. During the third month of life, the absolute increase in the experimental group was 6.07-5.34 kg (little lambs), and in the control group - 4.56-3.69 kg. The lambs spent the fourth month of life on alpine pastures, where the growth of the control group (6.47-5.62 kg) was lower than that of the experimental group (5.87-5.39 kg). The last month of the suckling period is characterized by a significant drop in the growth of lambs in the control group (3.16-2.88). The growth of lambs in the experimental group also decreased (4.83-4.67).

Economic substantiation of the production of sheep breeding products in the farms of Ukraine

Activation of the development of sheep breeding in Ukraine is possible based on the spread of specialized farms for breeding and growing sheep for meat, which will contribute to the economy of rural areas, employment, and welfare of the population. The article presents the main results of the research on planning the economic efficiency of the production of sheep products in farms, taking into account the market conditions of Ukraine. The optimal structure for the organization of production and sale of sheep products is proposed and substantiated, which includes breeding, growing, slaughtering sheep, and entering the market through direct sales channels with sheep meat, wool, sheepskin, and main by-products, which will significantly increase the profitability of the farm compared to traditional business models in sheep breeding, which are focused on breeding and rearing with the sale of animals in live weight. The planning of the need for fixed and working capital, which is necessary for the organization of production of sheep products in a family-type farm with several 200 ewes, has been carried out. The cost of production of sheep breeding products by main species was calculated, which at the beginning of the project was 2.8 euros for 1 kg of lamb, 1.4 euros for 1 kg of wool, and about 10 euros for one sheepskin. It was determined that the required amount of advanced capital for the organization of the farm would be 88 thousand euros, which will be compensated by net cash flow in 3 years. The farm is predicted to produce and sell products in the market for a total of 54,000 euros in the first year, which will potentially increase to 80,200 euros by the end of the project, which will fully compensate for costs and ensure a net profit of up to 20,000 euros EUR per year at the end of the project implementation period. The estimated amount of net cash flow for five years is EUR 77,000, with an internal rate of return of 26.3 %. The ratio of net cash flow to the cost of capital will be from 33 to 63 %, which justifies the relatively high level of investment efficiency in the production of sheep products in family farm farms following the technical and economic features of the business described in the article. The influence of the production volume of sheep breeding products on indicators of investment effectiveness is also determined. It has been established that an increase in the number of ewes from 200 to 500 will increase the net cash flow by an average of 15-16 thousand euros per year for every 100 head of increase in the number of sheep with a simultaneous decrease in capital costs per head.

Bio-economic modelling of sheep meat production systems with varying flock litter size using field data

Sheep meat producers derive the majority of income from sales of weaned lambs, determined by flock conception rates, litter size, and lamb survival. Field data from commercial flocks can inform sensitivity analyses of the effect of litter size on flock productivity, feed demand, and gross margin. This study adapted an established bio-economic model of a flock of breeding ewes informed by statistical relationships (from linear models) between flock litter size (lambs born per ewe lambing) and production factors (such as flock barren rate, litter birth type and lamb birth weight) identified using 156 145 animal records from the Irish national sheep breeding database. Sensitivity analyses were undertaken to investigate the effects of flock litter size on flock production, feed demand, and gross margin. Results showed that as flock litter size increased, the proportion of lambs born as multiples increased, with 14 % of lambs born as singles when flock litter size was 2.2 lambs born per ewe lambing. Flock gross margin increased from €2 205 to €7 730 as litter size increased from 1.0 to 2.0 lambs born per ewe lambing. As litter size increased from 1.0 to 2.2 lambs born per ewe lambing, flock gross margin increased linearly by, on average, €52 per 0.01 increase in litter size. At a litter size of > 2.2 lambs born per ewe lambing, flock gross margin increased on average €12 per 0.01 increase in litter size. At a litter size of 2.2 lambs born per ewe lambing, flock efficiency (at 65.0 kg of lamb weaned per ewe presented for breeding), weaning rate (at 1.5 lambs weaned per ewe presented for breeding; not including excess lambs from large litters sold within a week after birth and thus not weaned on-farm), and gross margin (at €8 500) began to plateau. The results indicate lower marginal returns in gross margin at very high flock litter size, due to the lower value of additional lambs born as triplets and quadruplets compared with single- and twin-born lambs. However, the diminishing economic returns occurred at higher flock litter size than are currently biologically achieved in most flocks. Quantification from this analysis demonstrates how the value of increasing the number of lambs born changes at very high flock litter size, which can inform the priorities and performance benchmarking for international sheep meat production industries.

Effect of maternal intrinsic factors on productivity and efficiency at weaning in commercial flock of Pelibuey ewes in the tropic of Tabasco, Mexico

Evaluation of ewe efficiency or productivity is a complex trait because of several factors that are related to produce heavy litters (lamb growth traits) per ewe. The objective of present study was to evaluate maternal intrinsic effects (body weight, body condition score, udder type, litter size, lamb sex) on litter growth traits (litter weight at lambing [LBW] and at weaning adjusted for 70 days [LWW70]) as a criteria of productivity and some indexes of efficiency in Pelibuey ewes. Data of body weight (BW), body condition scores (BCS), and udder types (UT) were taken at lambing, likewise at weaning BW (WBW), on 48 multiparous Pelibuey ewes. Additionally, litter size, sex, birth and weaning weight, were recorded for each offspring; this information was used to calculate LBW, LWW70, average daily gain (ADG), and the following indexes: Ewe efficiency (EEF) expressed as kg of lamb weaned per kg ewe BW at lambing, EEF0.75 expressed as kg of lamb weaned per kg ewe metabolic BW (BW0.75) at lambing, and EEF2 expressed as kg of lamb weaned ± ewe BW gained or lost at waning per kg ewe BW at lambing. For statistical analysis, ewes were classified according to BW (low, medium and high), BCS (low and high) and udder type (I, II, III and IV) at lambing. High BW ewes had greater (P? 0.01) LLW and LWW70 than low BW ewes. Ewe BW at lambing did not affect (P> 0.05) any productivity index. Also, BCS from lambed ewes did not alter (P> 0.05) the productivity parameters. The udder type affected only LWW70 and productivity indexes, being similar among ewes with type-I, II and III udders, but lower in ewes with type-IV udders. Likewise, double litters were heavier at birth and weaning than single litters, affecting EEF and EEF0.75, but not EEF. The Pelibuey ewe’s productivity in humid tropic depends on the maternal BW, udder type at lambing and prolificacy, being a better productivity when ewes have a high BW, double lambing and non-misshapen udders.

Foraging behaviour, digestion and growth performance of sheep grazing on dried vetch pasture cropped under conservation agriculture.

This study aimed to investigate the replacement value of half time grazing of wheat stubbles by vetch, which had been cropped under the context of conservation agriculture (CA). Three grazing treatments were evaluated on Barbarine lambs (initial BW 18±1.42kg). Treatment 1 consists of 6-hr grazing on dried vetch only (V). For treatment 2, the sheep were grazing 3hr on wheat stubbles in morning and 3hr on dried vetch in the afternoon (VWS). Treatment 3 consists of 6-hr grazing of wheat stubbles only (WS). At grain maturity stage, biomass yield of vetch averaged 7 tons DM/ha allowing a grazing period of 2 consecutive months. Along this period, vetch conserved its pods indehiscent. Biomass and nutritive value of vetch and wheat stubbles were decreasing from the start to the end of the grazing period. Residual biomass was higher in vetch and wheat stubble assigned to treatment VWS. WS lambs spent more time on walking and standing, while V and VWS lambs allocated more time on biomass uptake. The DM, OM and CP intakes were higher in animal grazing vetch alone or combined to wheat stubble. Rumen fermentation parameters (pH, ammonia nitrogen concentration and protozoa count) were not affected (p>.05) by any of the three treatments. The average daily gain of lambs on V and VWS lambs was three times greater (p<.05) than that of WS lambs (164, 152 and 49.5g respectively). Cold carcass yield averaged 444, 428 and 388g/ kg for lambs assigned to V, VWS and WS treatments respectively. It is concluded that grazing vetch alone or combined with WS increased substantially the growth performance and carcass yield of lambs compared with WS grazing only. Therefore, dried vetch grazing could be a solution to make possible mulching and biomass uptake by sheep under the context of CA.

Evaluation of estrous synchronization protocols on ewe reproductive efficiency and profitability

A 2-year experiment was conducted to determine the effect of a single injection of prostaglandin after initiation of the breeding season on ewe estrous synchronization. Rambouillet ewes (n = 101; Year 1 = 52; Year 2 = 49) assigned to one of three treatments: untreated (CON); 12-d CIDR insert (CIDR); or 1 injection of prostaglandin at d 2.5 (1 PG) after rams were placed with ewes. Rams were placed with ewes at the time of CIDR removal (d 0) and remained with ewes during a 35-d breeding season. Both the CIDR- (94%) and 1 PG (73.5%) treatment groups had a larger number (P ≤ 0.01) of ewes bred in the first 5 d of the breeding season compared to ewes of the control (33%) group. As expected, CIDR-treated ewes had a shorter time to mating, than 1 PG-treated ewes and ewes of the control group had a longer interval to mating than both CIDR- and 1 PG-treated ewes (P ≤ 0.01). The number of lambs born per ewe and kg of lamb weaned per ewe was not different (P ≥ 0.31) among treatment groups. Additionally, there was no difference (P = 0.78) in net profit per ewe among treatment groups. Based on these data, utilizing a single injection of PG 2.5 d after initiation of the breeding season resulted in similar pregnancy rates at d 5 of the breeding season when compared with CIDR-treated ewes indicating the potential utilization of the 1PG protocol in a confinement setting as a viable method for estrous synchronization.

Factors affecting the productivity and the efficiency at weaning of hair ewes in a dry tropical environment

The aim of the study was to evaluate the productivity and efficiency of ewes, relative to the body weight and metabolic body weight in four hair sheep breeds. The dataset included the records of litter size, parity number, birth weight, weaning weight, age at weaning, and ewe body weight (EBW), recorded 24 hours after lambing, from 926 purebred ewes. In total, there were 1,198 lambing records (114, 86, 434 and 564 for Blackbelly, Dorper, Katahdin and Pelibuey, respectively). Ewe metabolic body weight at lambing was calculated as EBW0.75. Ewe productivity was evaluated at weaning, and ewe efficiency as the ratio of kg of lamb produced at weaning (adjusted at 60 d of age) divided by ewe body weight or EBW0.75, respectively. Katahdin and Dorper ewes had greater body and EBW0.75 compared to Blackbelly and Pelibuey ewes (P&lt;0.05). There was no difference for those traits between Blackbelly and Pelibuey ewes (P&gt;0.05). Katahdin weaned heavier litters than the other breeds (P&lt;0.05); however, there were no differences between breeds for ewe efficiency at weaning (P&gt;0.05). Third parity ewes were more efficient than both early and late parity ewes (P&lt;0.05). Lambing season was a significant source of variation for ewe efficiency (P&lt;0.05). Under the conditions of this study, ewe efficiency could be increased by weaning more than one lamb.

Effects of starvation and realimentation on the performance of pregnant ewe

Twenty pregnant ewes were used in this study. Ten pregnant ewes with a mean live weight of 19.37 Kg ±0.87 served as the control animals, the others with an average live weight of 19.50 Kg ± 0.37 were starved for 7 days to study the reproductive performances, feed intake and appetite, body weight and rate of recovery in the animals. Test animals were starved during the first week of the last trimester of pregnancy (16th week). Starvation did not cause any significant changes in gestation length, which was within the normal range of 146 to 149 days. A live weight loss of 3.20% was observed during the starvation period. As the starvation progressed, the animals became weak and dull in appearance. Their hairs became loose and tended to fall out. Moreover, as from the 5th day of starvation, they were in a semi-comatose condition and were observed to sway when made to walk. Starvation also resulted in lower (P&lt;0.05) birth weight of lambs:2.05 ± 0.05 kg for lambs from starved ewes compared to 2.25 + 0.10 Kg for lambs from the control pregnant ewes. However, subsequent growth of all lambs produced during the study was not appreciably affected. On resumption of ad libitum feeding appetites as Dry matter intake was low and erratic for 4-6 days. There after feed intake returned to normal with a marked increase in live weight gain.Bang. J. Anim. Sci. 2016. 45 (2): 35-40

Economic evaluation of the termination of lambs in pasture&#x0D;

The present study it had for objective to evaluate the economic viability of the termination of lambs in pasture cultivated of Lotus subbflorus cv. El Rincón and annual Azevém (Lolium multiflorum Lam.) in 10 hectares, the Sant´Ana Farm, city of Herval, RS. For the costs of the pasture and the commercialization had been in such a way evaluated; gain of body weight and productive characteristics of 225 lambs, separate in ten lots. The first lot of animals entered in the pasture in 02/07/2003 and the last one left in 23/11/2003, in a total period of 145 days, with average capacity of 71,7 lambs. On average the lambs had entered in the pasture with body weight of 24,110 kg and had left with 33,120 body weight of kg in a period of 48,2 days to reach the condition of abate. Important variation in the gain body weight of the lambs was evidenced, enters inside and of races. In 145 days of use of the pasture 2,042 had been produced, 74 kg of lamb. The total cost of the pasture was of R$4.065, 00 and the rude return for and the gain of the lambs of R$6.741, 36. In this way, it was gotten yield of 65,84% of the invested value and gain of R$2.676, 36. In this direction the termination of lambs for meat production, in cultivated pasture was viable economically.

Life cycle assessment of animal origin products

Greenhouse gas emissions from livestock production have a major impact on the environment. Life cycle assessment (LCA) is an accepted method to assess those environmental impacts associated with all stages of products life from cradle to grave, and is used to determine the carbon footprint (CF) of animal origin products. CF is just an environmental indicator to assess sustainability of livestock products, such as milk, beef, pork, chicken, eggs, etc. and is used on products packaging as a so-called carbon label to inform supply chain professionals about the relative impacts of different products and activities. From the published studies who assessed the impact of production of milk, beef, lamb, pork, chicken and eggs using LCA, it is concluded that production of 1 kg of beef used most land and energy and had highest global warming potential, followed by production of 1 kg of lamb, pork, chicken, eggs and milk. However, it should be pointed out that LCA results for livestock products do not include environmental consequences of competition for land between humans and animals, and consequences of land-use changes.

Matrizes ovinas cruzadas são sempre mais eficientes do que as matrizes puras?

Foi estudado o desempenho reprodutivo de 482 ovelhas multíparas (3/4 Texel x 1/4 Corriedale: TXC, 1/2 Romney Marsh x 1/2 Corriedale: RMC, 3/4 Poll Dorset x 1/4 Corriedale: PDC, 1/2 Finnish Landrace x 1/2 Merino Australiano: FLMA e Merino Australiano puras: MA), as características do crescimento de 585 cordeiros provenientes de carneiros Dorper e ovelhas: TXC (n = 68); RMC (n = 64); PDC (n = 68); FLMA (n = 183) e MA (n = 202) e os quilogramas de carne de cordeiros produzidos/kg de ovelha colocadas em cobertura (como indicador de eficiência), pastoreando campo natural e pastagens cultivadas. As ovelhas FLMA e TXC apresentaram as maiores taxas de parição (167,89 e 174,36%, respectivamente) em relação às demais cruzas, as quais não diferiram entre si (121,43 e 125,49%, PDC e RMC, respectivamente; P&gt;0,05), porém foram superiores as MA (88,99%), sendo esse resultado uma consequência da maior quantidade de cordeiros nascidos/ovelha parida, que influenciou mais do que sua maior taxa de fertilidade. O genótipo da ovelha também afetou (P&lt;0,0001) o crescimento dos cordeiros até o momento da sua venda com 41,6 ±6,7kg aos 206±7,25 dias de idade. Os cordeiros filhos das ovelhas TXC, PDC e RMC apresentaram maiores ganhos de peso diário que os filhos de FLMA, e esses maiores do que os MA. No entanto, de todas as cruzas avaliadas, somente a FLMA foi mais eficiente que a MA.

EFFECT OF VITAMIN E SUPPLEMENTATION ON THE PRODUCTIVE PERFORMANCE OF RAHMANI SHEEP

The present study was conducted during the period from (September 2012 to April 2013) at the experimental farm station, belongs to Anim. Prod. Dept., Fac. of Agric., Al-Azhar Univ. Thirty pregnant Rahmani ewes with an avg. 33.7 kg LBW and 3 years old age were used to investigate the effect of vitamin E daily supplementation to pregnant ewes at late gestation and early lactation on the productive performance of treated ewes and their offsprings. Experimental animals were randomly assigned (28 days prepartum) to three nutritional groups; the 1st one served as a control (nil vitamin E supplement). The 2nd and 3rd groups were daily and individually administrated 400 IU of α-tocopherol acetate (vitamin E), 28 days prepartum (T1) and for 28 days pre and 28 days postpartum (T2). Experimental animals were offered their daily requirements during pregnancy and early lactation according to NRC recommendations (1985). Results obtained showed that; supplementing pregnant ewes with vitamin E didn’t lead to any positive influences on improving their daily milk yield or milk chemical composition, although there were significant differences among different experimental groups in daily milk yield. Ewes of T2 recorded higher (p<0.05) daily milk yield (417 g /h/d) in compare with (348 g /h/d) for the control ewes group and (292 g /h/d) for T1 ewes, respectively. Vitamin E supplementation to pregnant and lactating ewes didn’t lead to significant differences in most of daily milk yield and chemical composition traits. Although, there were significant differences among different ewes groups in fat and SNF percentages in favor of the two supplemented ewes groups. Vitamin E supplementation to pregnant and lactating ewes didn’t improve productive performance of both the two supplemented ewes groups and their progenies. Ewes of T1 group weaned more (p<0.05) kg of lambs, but without significant difference with those of the control group. Ewes of T2 weaned lower (p<0.05) kg lambs. Ewes of T2 and the control group one indicated more efficient feed utilization in compare with T1 group. Vitamin E supplementation didn’t improve (p<0.05) lambs productive performance. Although, there were significant differences among different lambs groups in lambs avg. weaning weight, daily gain and lambs feed conversion ratio. Lambs born to T2 ewes consumed (p<0.05) higher milk intake (417 g/h/d), but lower feed conversion ratio (3.06 kg MI/kg gain), while lambs born to T1 ewes consumed lower milk (292 g/h/d), but with an improved FC ratio (1.75 kg MI /kg gain). Lambs born to the control ewes group consumed (348 g/h/d), but with more efficient FC ratio (2.20 kg milk intake / kg gain) in comparison with the corresponding lambs born to T2 ewes groups. Lambs born to T1 supplemented ewes recorded higher (p<0.05) avg. weaning weight (13.73 kg/h) and faster daily weight gain (179 g/h/d), without significant difference with lambs born to the control ewes group (165 g/h/d), while lambs born to T2 supplemented ewes indicated lower weaning weight (11.40 kg /h) and slower daily weight gain (141 g/h/d).

Genetic improvement of hill sheep – Impacts on profitability and greenhouse gas emissions

Scottish Blackface hill sheep from two research flocks, based in environments of differing climatic severity, were selected for 8 years based on a selection index incorporating ewe and lamb traits, designed to improve flock sustainability and profitability. Compared to a control line of sheep kept at average performance, after 8 years of selection, sheep selected on this index have shown increased overall profitability, largely due to an increase in the weight of lambs at weaning (2–2.5kg, depending on farm). A model was used to estimate greenhouse gas (GHG) emission changes in hill sheep systems when performance traits were altered, to investigate the potential to use genetic selection as a tool to reduce GHG. Results from this model suggested that the actual genetic changes observed in the hill flocks are likely to have increased GHG emissions, both at the level of the breeding ewe and per kg of lamb produced, mainly as a result of an increase in ewe mature size (2.8–3kg difference vs. the control line after 8 years of selection). Any future selection index designed to minimise GHG emissions, would need to incur heavier penalties for increasing ewe mature weight, compared to the current economic index, which would be likely to reduce selection response in lamb growth. These changes are only likely to occur if payment or subsidy systems were to change in a way that would reward producers for reducing GHG emissions.

Performance of purebred Welsh Mountain and crossbred ewes in a hill environment

The aim of this study was to compare the body weights, body condition scores, survival and litter weights of lamb produced by pure Welsh Mountain ewes with those of crossbred Cheviot, Lleyn, Poll Dorset and Texel ewes in a hill environment. Ewes were mated to Suffolk rams and recorded over the first 3 seasons of production. Between lambing and weaning, ewes rearing single lambs grazed semi-natural hill swards (1.5ewes/ha) and those rearing twins grazed improved enclosures (10ewes/ha). Crossbreeding significantly (P<0.001) increased body weights at all ages, with values for four-year old ewes of 45.9, 57.2, 51.6, 57.8 and 58.5kg in purebred Welsh Mountain and Cheviot, Lleyn, Poll Dorset and Texel crossbred ewes respectively. Individual lamb growth rates from birth to 8 weeks and from 8 weeks to weaning were significantly higher in the progeny of crossbred ewes (P<0.001) with highest growth rates for lambs reared by Poll Dorset and Texel cross ewes. Individual lamb weaning weights were 27.0, 29.4, 29.2, 30.4 and 30.7kg for lambs reared by purebred Welsh Mountain and Cheviot, Lleyn, Poll Dorset and Texel crossbred ewes respectively. Survival rates to third mating were 0.73, 0.77, 0.83, 0.72 and 0.75 (P<0.05), litter size reared was 1.22, 1.33, 1.49, 1.43 and 1.25 (P<0.001) and litter weights at weaning were 37.1, 43.5, 46.1, 46.5 and 44.2 (P<0.001) for purebred Welsh Mountain and Cheviot, Lleyn, Poll Dorset and Texel crossbred ewes respectively. Efficiency expressed as kg litter weight/kg ewe pre-tupping weight0.75 was significantly improved (P<0.001) by crossbreeding. Total litter weight at weaning over three lamb crops per ewe entering the flock was increased from 78.4kg in purebred Welsh Mountain ewes to between 97.1kg in Cheviot and 109.7kg in Lleyn crossbred ewes. It is concluded that where feed resources are adequate, the retention of crossbred ewes in the hill flock can give significant improvements in productivity.

Effect of body condition score and body weight of Sanjabi ewes on immune system, producti ve and reproducti ve performance

Total 80 Sanjabi ewes (2–5 years old and 50–85 weight domain) were selected in animal unit of Mehregan farm. The ewes were divided to 4 treatment groups according to body condition score of (2, 2.5, 3, 3.5 ≤). Blood samples were collected from non-pregnant ewes, then after mating, two weeks before expected lambing and at lambing day. Blood samples of newborn lambs were also taken from the jugular vein at birth and 7 days of age. The reproductive parameters such as number of lambs born per lambing, kg of lambs born per ewes mating, pregnancy period and lamb birth weight were determined. Some blood metabolites such as glucose, total protein, albumin and globulin were determined. The white blood cell and differential leukocyte counts were also measured. The result of this experiment indicated that BCS = 3 had a significant effect (P &lt; 0.05) on the kg lambs born per ewes. Ewes with BCS = 3 had a better performance in the percentage of lambs born per ewes at mating, while the lambing rate reduced in ewes with BCS of 3.5 or more. Birth weight of lambs was significantly affected by BCS of their ewes (P &lt; 0.05). There was a significant effect of BCS on plasma FSH concentration in ewes with BCS more than 3 but no significant difference was seen in blood metabolite in this study. Colostrum productions and the lamb birth weights were affected by body condition score of ewes. The white blood cell counts, neutrophils and lymphocytes counts did not change between ewes and lambs. It is concluded that BCS had a significant effect on kg lambs born per ewes, birth weight of lambs, lambs weaning weight and colostrum productions (P &lt; 0.05) and the score of 3 at mating time could optimize profitability of Sanjabi ewes.

A field study of reproductive performance and productivity of Pelibuey ewes in Southeastern Mexico

The objective was to evaluate the reproductive performance and productivity of Pelibuey ewes in two flocks in Southeastern Mexico. Animals grazed on irrigated star grass (Cynodon plectostachyus). In flock 1, lambs grazed with their mothers from 7 to 70days of age (weaning age), whereas in flock 2, they were confined and offered chopped grass, a commercial concentrated and managed under restricted suckling until weaning at 60days of age.. The statistical model included the fixed effects of flock, year and season of lambing, parity number, litter size at weaning, first order interactions and the random effects of ewe and the error term. The means ± SD for age at first lambing, prolificacy, lambing interval (LI), weaning weight, and productivity were 477 ± 85.5days, 1.41 ± 0.51 lambs, 255.9 ± 51.8days, 16.5 ± 4kg, and 18.1 ± 4.42kg of lamb weaned, respectively. Repeatability estimates for the latter four traits were 0.09, 0.07, 0.11, and 0.13, respectively. All main effects in the models were significant (P < 0.001), except for year on LI. Prolificacy and productivity increased with parity number. The shortest LI was in the rainy season. Ewes with two or three lambs produced 8 and 14kg of lamb more at weaning than single lamb ewes. In conclusion, reproductive performance and productivity could be improved, and the low repeatability estimates suggest that management should be used in a short term rather than genetic approaches.

The effects of parturition season and suckling mode on the puerperium of Santa Ines ewes and on the weight gain of lambs

Seventy-seven ewes were randomly divided into groups according to parturition season and suckling mode [Rainy season: continuous (n=14) and controlled (n=13); Dry season: continuous (n=25) and controlled (n=25)]. The controlled suckling mode, in both seasons, resulted in a decrease in variables, intervals between parturition and first estrus (reduction of 27.11 and 11.46 days for rainy and dry season, respectively; P&lt;0.05) and between parturition and estrus of conception (reduction of 12.81 and 13.58 days, for rainy and dry season, respectively; P&lt;0.05). As to the lambs, the weight gain was higher in animals subjected to controlled suckling in relation to continuous, especially when lambing occurred in the rainy season (17.83±0.56 vs. 13.95±0.52kg for Lambs' weight at 90 days old, respectively; P&lt;0.05). Therefore, it was concluded that controlled suckling management is better indicated for the Amazonian region, since it allows the ewes to have a shorter puerperium period and the lambs exhibit higher weight gain.

Carcass and Non-carcass Components of Priangan and Javanese Fat-tailed Rams Slaughtered at Mature Live Weight

Twenty-three of indigenous Priangan and Javanese Fat-tailed (JFT) ram breeds were used to evaluate its carcass and non carcass components slaughtered at mature live weight. Five Priangan rams and six JFT rams were slaughtered at 32.5 kg of live weight while six other rams of each breeds were also slaughtered at 40 kg of live weight. Before the rams were slaughtered, they werefattened using pellet ration which was formulated according to NRC for fattening 10 kg of lamb, containing 73.3% TDN and 16% protein in dry matter bases. Feed and water were given ad libitum. Rams were slaughtered and dissected when they reached their assigned slaughter weight (32.5 and 40 kg). The results showed that both breeds had high percentage of carcass (53%-55%) with no significantly different between breeds (P &gt; 0.05) either were slaughtered at 32.5 kg or 40 kg. However, carcass of Priangan rams had significantly more muscle, but less fat than Javanese Fat-tailed rams at mature live weight (P &lt; 0.05). Non-carcass components were not significantly different between breeds (P &gt; 0.05) except for head, tail and testes (P &lt; 0.01) and liver (P &lt; 0.05). The edible and inedible portion of non-carcass rangedfrom 30%-32% and 12%-15% of slaughter weight, respectively.

PHYSIOLOGICAL RESPONSES OF SHEEP TO DIET SUPPLEMENTATION WITH YEAST CULTURE

ABSTRACTThe effect of dietary yeast culture (YC) supplementation during pre-mating and gestation periods on some physiological responses was studied in 48 Suffolk crossbred ewes aged 3-4 years and weighed 58.54 ± 1.34 kg. The animals were divided into 3 comparable groups. The 1st group was fed a basal ration composed of 60% concentrate feed mixture (CFM) plus 40 % clover and rice straw. The 2nd and 3rd groups fed the same basal ration which supplemented daily with 2.5 or 5.0 g YC added to a part of the ground CFM, respectively. Results showed that YC supplementation improved significantly (P<0.05) reproductive ability, prolificacy, lambs born/ewes joined, lambs weaned/ewes lambed, kg of lambs born or weaned/ewes joined or /ewes lambed and insignificantly affected conception rate, fertility, fecundity and twinning frequency compared to those of control ewes. It also resulted in higher (P<0.05) serum albumin, glucose, urea concentration and AST activity but it decreased cholesterol concentration (P<0.05) than control ewes. Serum albumin and urea did not significantly differ among gestation periods. However, total protein, globulin, glucose and cholesterol concentrations progressively increased (P<0.05) with the advancement of pregnancy especially up to the 15th week of gestation followed by a decrease up to lambing. The A/G ratio showed an opposite trend (P<0.05), meanwhile creatinine concentration and activity of AST and ALT were fluctuated. Rectal and skin temperatures, pulse rate and respiration rate were lower (P<0.05) in YC supplemented ewes than those in control ones. It can be concluded that yeast culture supplementation could be safely added to ewes ration at 5.0 g /d/head during pre-mating and gestation periods in order to improve the reproductive performance, blood components and thermo-cardio-respiratory responses without any adverse effects on liver and kidney functions.

Meta-analysis to establish the response of having heavier mature ewes during gestation on the birthweight of the lamb and the weaning weight of the ewe and lamb

There is much uncertainty about feeding ewes to maximise the performance of progeny and of the ewe itself to weaning. This includes questions about feeding the ewe to influence the lamb’s birthweight for lamb survival, feeding to augment the ewe’s lactation to maximise the lamb’s growth potential before weaning and feeding the ewe to increase the probability of having multiple offspring. The objective of this study was to carry out a meta-analytic study to consider the response of having heavier mature ewes during gestation on lamb and ewe performance measured by birth and weaning weights. The birthweight of singleton lambs was the greatest, twins were intermediate and triplets the lowest (5.8, 4.8 and 4.1 kg, respectively; P &lt; 0.001). A similar trend (P &lt; 0.001) was observed for the weaning weight of the lamb (29.1, 25.2 and 23.7 kg for lambs weaned as a single, twin or triplet, respectively). The liveweight of ewe at weaning was greater (P &lt; 0.001) for those ewes that failed to wean a lamb (69.6 kg) or weaned a single lamb (67.8 kg) compared with ewes that weaned twin and triplet lambs (64.8 and 65.3 kg; respectively). A greater ewe liveweight during gestation gave different responses on the lamb birthweight, lamb weaning weight and the weaning weight of the ewe and this was dependent on birth and weaning rank category of the lamb (P &lt; 0.05). Overall, the response of heavier ewes on lamb birthweights and ewe and lamb weaning weights was small compared with the effect of birth and weaning rank of the lamb.