Post-weaning Average Daily Gain Research Articles

Providing additional objects to straw reduces piglets’ redirected behaviour post-weaning but influences weight gain pre-weaning negatively

ABSTRACT We investigated the post-weaning effect of providing additional objects (i.e. rope, ball, tyre) to commercial piglets given straw pre- and post-weaning on behaviour and average daily gain (ADG). Piglets from litters with objects (O, n = 20 in 5 litters) and controls (C, n = 20 in 5 litters) were observed from 24 h post-weaning and during six days. Piglets were weighed at birth, weaning and 11 days post-weaning. O-piglets performed less littermate manipulation (P < 0.05), exploring pen fixtures (P < 0.1) and lying (P < 0.1) but spent more time in the creep post-weaning than C-piglets (P < 0.1). Social or locomotor play was expressed similarly in both treatments. Day strongly influenced the behaviour of pigs post-weaning. O-piglets had significantly lower pre-weaning ADG than C-piglets (P < 0.05), but there was no significant difference in post-weaning ADG between the treatments. Providing objects to piglets around weaning may reduce some negative behaviours, but may affect weight gain negatively.

167 Evaluation of an out-of-season breeding system for organic lamb production in missouri

Abstract Organic production is one of the fastest growing food and agriculture industry. The seasonality of lamb production affects lamb markets and prices, whereas, an out-of-season breeding and organic fall lamb production scheme may enhance product availability and competiveness. Six rams and 100 Katahdin ewes were selected for an out-of-season breeding during April and May of 2017 and 2018, for two production years. Ewes were synchronized for estrus using CIDR® device (EaziBreed™) (12 d) before breeding and fed ‘flushing’ feed for four weeks. Ewes were bred in mixed sire groups for two estrus cycles (35 d). Animals were rotationally grazed and maintained good body condition score (3.0) throughout the seasons at certified organic farm in Missouri. Mean live weight measured monthly from breeding to lambing were 57.8, 60.1, 62.1, 64.7, and 59.3 kg. Eighty nine ewes lambed in fall 2017 giving birth to 121 lambs (136% lambing rate) and eighty eight ewes lambed in 2018 giving birth to 126 lambs (143% lambing rate). Ninety seven percent of weaned lambs were maintained as an organic production status for marketing. Lamb birth weight, average daily gain weight, weaning weight, and 30 d post weaning weight, post weaning average daily gain weight were recorded for 2017 born lambs as 3.74±0.03 kg, 21.00±0.24 kg, 24.78±0.28 kg, 176±2 g/d respectively. Organic weaner lambs were sold for 5 to 15% higher price values (P &amp;lt; 0.05) per unit than non-organic peer groups at a local livestock auction sale.

Association of growth performance and body conformational traits with BMP4 gene variation in Barki lambs

The objective of this study was to test the association of the variation in a 360 bp region in exon 2 of the ovine bone morphogenetic protein 4 (BMP4) gene with growth performance (birth weight, pre-weaning average daily gain, weaning weight, post-weaning average daily gain and marketing weight) and body conformational traits (height at withers, height at hips, body length, heart girth, thigh circumference, body mass index, skeletal muscle index, body index and relative body index) in 242 Barki lambs using polymerase chain reaction-single strand conformational polymorphism (PCR-SSCP). Two variants (A and B) and three genotypes (AA, AB and BB) were detected. The BMP4 genotype significantly affected (p < .05 or p < .01) post-weaning daily gain, marketing weight, height at hips, thigh circumference, body mass index and skeletal muscle index. The results provided valuable information indicating selection for the BMP4 genotype might increase growth and muscularity in Barki lambs.

Factors affecting post-weaning average daily gain and kleiber ratio in Muzaffarnagari sheep

Data on 3693 Muzaffarnagari lambs born during 1992–2014 at ICAR-Central Institute for Research on Goats, Makhdoom (Uttar Pradesh) were analyzed to assess the influence of period, season, parity, type of birth, sex and dam's weight at lambing on post-weaning growth and Kleiber ratio (KR). The overall least squares means of average daily gain during 3–6 months (ADG1), 6–12 months age (ADG2), KR from 3–6 months (KR1) and KR from 6–12 months (KR2) were 85.80±0.82 and, 43.70±0.56 g, 8.10±0.06 and 3.30±0.04 g/kg body mass, respectively. The effects of period, season, type of birth, sex and dam's weight at lambing were significant (P<0.01) on all ADGs and KRs except non-significant influence of season on ADG2 and KR2. Parity of dam had nonsignificant influence on all traits. The results indicated declines in growth rate and Kleiber ratio with the advancement of age and the environmental factors, should be given weightage in the management of flocks. Therefore, for achieving higher body weight gains in Muzaffarnagari sheep selection should be made at 6 months age.

A randomized controlled trial to evaluate performance of pigs raised in antibiotic-free or conventional production systems following challenge with porcine reproductive and respiratory syndrome virus

The trial objective was to compare the performance and animal health parameters of pigs raised according to one of 3 antibiotic (AB) protocols: standard AB medication consisting of mass treatment on days 4 and 21 and judicious AB therapy given therapeutically thereafter as group medication in water and feed or by individual injection (group T1, N = 702); modified AB medication identical to group T1 but with mass treatment only on day 4 and without subsequent therapeutic feed medication (group T2, N = 675); or an antibiotic-free (ABF) regimen (group T3, N = 702). All pigs were vaccinated with a modified-live porcine reproductive and respiratory syndrome virus (PRRSV) vaccine 3 days after weaning. Using a seeder pig model to mimic endemic field infection dynamics, pigs were contact-challenged with virulent PRRSV lineage 1 strain 174 four weeks after vaccination. At finishing, average daily gain (ADG) and mean feed conversion ratio (FCR) were significantly better (p ≤ 0.05) for the T1 and T2 groups compared to the T3 group. There were no significant differences in post-weaning ADG and FCR between the T1 and T2 groups. Mortality and removals significantly favored (p ≤0.05) the T1 and T2 groups (20.94% and 24.89%, respectively) versus the T3 group (57.98%). Net revenue per pig was $105.43, $98.79, and $33.81 for the T1, T2 and T3 groups, respectively. Under the conditions of this study, these results indicate that in a PRRSV-endemic setting involving bacterial co-infections, an ABF production strategy may leave pigs at considerable risk of exposure to severe clinical disease and that judicious use of antibiotics can significantly improve animal health.

A genetic evaluation of growth, ultrasound, and carcass traits at alternative slaughter endpoints in crossbred heavy lambs.

Genetic parameters were estimated for growth, ultrasound, and carcass traits in a Canadian crossbred heavy lamb population. Traits analyzed included birth, weaning, post-weaning, and ultrasound scanning weights; pre- and post-weaning average daily gain; ultrasonically measured eye muscle and fat depths; hot carcass weight; fat depth at the GR site (110 mm from the midline on the 12th rib); carcass conformation scores; saleable meat yield; price grid value; and total carcass value. The impact of three alternative slaughter endpoints (slaughter age, carcass weight, and carcass fatness) on genetic parameter estimates was also evaluated. In general, carcass traits were found to be moderately heritable, with heritability estimates ranging from 0.17 ± 0.02 for hot carcass weight at a constant slaughter age to 0.34 ± 0.02 for average carcass conformation score at a constant carcass weight. Heritability estimates were similar when observations were adjusted to alternative slaughter endpoints, but for some traits, phenotypic variance and genetic correlation estimates differed. Genetic correlations between carcass traits and growth and ultrasound traits were typically favorable. Ultrasonically measured eye muscle depth and fat depth were found to be moderately to strongly positively correlated with hot carcass weight (0.33 ± 0.15 to 0.71 ± 0.19) and fat depth at the GR site (0.38 ± 0.14 to 0.74 ± 0.12), respectively, reaffirming the usefulness of selection on ultrasound traits to improve carcass yield and quality. Genetic correlations among carcass traits were generally favorable, with the exception of moderate unfavorable positive genetic correlations between fat depth at the GR site and primal cut carcass conformation scores (0.31 ± 0.05 to 0.60 ± 0.05). Overall, the results of this research suggest that there is potential to improve carcass yield and quality through genetic selection and provides the population-specific genetic parameter estimates needed for the genetic evaluation of carcass traits in the Canadian sheep population. Nevertheless, the optimal endpoint for carcass trait genetic evaluations will need to be further investigated, considering both the current findings and additional information on production practices in the industry.

Performance, rumen fermentation and blood metabolites of dairy calves fed starter mixtures supplemented with herbal plants, essential oils or monensin.

This study evaluated the supplementation effects of three herbal plants (thyme [THY], eucalyptus [EUC] and celery [CEL]), a commercial phytogenic additive ‎containing essential oils (PFA-EO, Digestarom® P.E.P.) and monensin (MON) in calf starter on performance, rumen fermentation and blood metabolites during pre- (days 3-55) and post-weaning (days 56-70). Sixty-six Holstein dairy calves (3 days of age, 41.2±3kg of BW) were allocated to one of six starters supplemented with: (i) no additives (CON), (ii) MON (30mg/kg), (iii) THY (23g/kg), (iv) CEL (23g/kg), (v) EUC (23g/kg) and (vi) PFA-EO (3g/kg). All the calves were offered starters ad libitum plus 6L of whole milk daily. Starter intake tended to be the highest in calves fed PFA-EO and THY; intermediate in calves fed CON, MON and EUC; and the lowest in those fed CEL. Average daily gain (ADG) and feed efficiency (FE) remained unaffected by dietary treatments during the pre-weaning. During the post-weaning period, ADG and FE ‎were greatest in calves fed EUC followed by those fed CON, MON, PFA-EO and THY, and then in those fed CEL. No differences were observed among the treatments in skeletal growth, faecal score, rumen pH or ammonia-N concentration. Compared to calves fed CON and MON, those fed the herbal plants or PFA-EO tended to recorded higher molar proportions of acetate and butyrate, and the acetate: propionate ratio. Blood malondialdehyde level did not differ among treatments, but calves on CON had the highest glucose concentration, and those fed PFA-EO recorded the highest value for β-hydroxyl butyrate on day 70. In conclusion, the results indicate that the three herbs and PFA-EO are capable of modulating some of the rumen fermentation parameters and blood metabolites as well as eucalyptus could potentially be a better alternative to monensin for improving post-weaning performance.

Crecimiento post-destete de corderos de pelo puros y cruzados bajo condiciones del trópico Mexicano

The study evaluated the post-weaning growth of pure and crossbred hair lambs under the tropical conditions of the southeast of Mexico. Data from 323 male lambs of six distinct breed groups (Dorper, Katahdin, Pelibuey, Dorper × Katahdin, Dorper × Pelibuey and Katahdin × Pelibuey) were analyzed. The dataset considered the post-weaning average daily weight gain (ADG) and final body weight adjusted to 60 (P60) and 90 (P90) days of fattening. The statistical model included the fixed effects of breed group and two seasons of the year (Dry: January-May and Rainy: June-September). The initial body weight was included as co-variable. Breed group was a significant source of variation for all the traits (P≤0.01), but the season of the year had no effect on any variable evaluated (P>0.05). Dorper × Katahdin crossbred lambs had a better post-weaning growth than the other breed group. Under the conditions of this study, genetic factors had a greater influence on the post-weaning growth of hair lambs than the non-genetic factors.

Growth and prolificacy performance of Garole sheep raised under semi-arid conditions

The growth and prolificacy performance of Garole sheep reared under semi-arid conditions at ICAR-Central Sheep and Wool Research Institute, Avikanagar, Rajasthan was evaluated in the present study. The body weight records of 1,058 lambs and prolificacy records of 624 ewes collected over a period of 19 years (1997-2015) were analyzed. The overall least squares mean for body weights at birth (BWT), 3 month (3WT), 6 month (6WT), 9 month (9WT), 12 month (12WT), pre-weaning (0-3 month) average daily gain (ADG1) and post weaning (3-6 month) average daily gain (ADG2) were 1.18±0.02 kg, 6.42±0.12 kg, 9.87±0.18 kg, 11.77±0.25 kg, 13.74±0.32 kg, 56.87±1.22 g and 40.19±1.39 g, respectively. The effect of sex of lamb, period of birth and dam weight at lambing were significant for all growth traits. Significant variation in growth performance, multiple birth and litter size was observed over the period. The body weight and average daily gain of Garole sheep improved over the years. In last 15 years, improvement ranging from 19.56 to 29.51% was observed for various growth traits studied. The multiple births in Garole ewes were 58.01% with a litter size of 1.68 at birth. The prolificacy and litter size in semi-arid conditions were similar to the native tract especially in initial period. Period of lambing and weight of dam at lambing significantly affected litter size at birth. Results showed that Garole performed well in the semiarid conditions and can be successfully reared in these conditions with updated management.

Abrupt weaning reduces postweaning growth and is associated with alterations in gastrointestinal markers of development in dairy calves fed an elevated plane of nutrition during the preweaning period

The benefits of feeding elevated quantities of milk to dairy calves have been well established. However, there is a reluctance to adopt this method of feeding in commercial dairy production because of concerns around growth, health, and ruminal development during weaning. The objective of this study was to characterize the effect of an abrupt (0 d step-down) or gradual (12 d step-down) feeding scheme when calves are fed an elevated plane of nutrition (offered 1.35 kg of milk replacer/d). For this experiment, a total of 54 calves were randomly assigned to an abrupt or a gradual weaning protocol before weaning at 48 d of life. Calves were housed and sampled in individual pens for the duration of the experiment, and milk, starter, and straw intake were measured on a daily basis. Body weight was measured every 6 d, whereas blood, rumen fluid, and fecal samples were collected on d 36 (pre-step-down), 48 (preweaning), and 54 (postweaning) of the experiment. Although the growth rates of the step-down calves were lower from d 37 to weaning (0.62 ± 0.04 vs. 1.01 ± 0.04 kg/d), the postweaning average daily gain was greater compared with the group that was abruptly weaned (0.83 ± 0.06 vs. 0.22 ± 0.06 kg/d). Total ruminal volatile fatty acid was greater in the step-down group on the day of weaning (d 48; 59.80 ± 2.25 vs. 45.01 ± 2.25 mmol), whereas the fecal starch percentage was lower during postweaning compared with the abruptly weaned calves (d 54; 3.31 ± 0.76 vs. 6.34 ± 0.76%). Analysis of the digestive tract of bull calves on d 55 revealed minimal differences between gross anatomy measurements of gut compartments as well as no morphological differences in rumen papillae development, yet the total mass of rumen when full of contents was larger in the step-down calves (7.83 ± 0.78 vs. 6.02 ± 0.78 kg). Under the conditions of this study, the results showcase the benefits of a step-down feeding strategy from an overall energy balance standpoint, due to increased adaptation of the gastrointestinal tract preweaning.

Performans Pertumbuhan Kambing Boerawa di Village Breeding Centre, Desa Dadapan, Kecamatan Sumberejo, Kabupaten Tanggamus, Provinsi Lampung

&lt;p&gt;The objective of research were to evaluate grading up program of Boer buck and Ettawa grade goat (EGG) doe at Village Breeding Centre (VBC) Dadapan village, Sumberejo subdistrict, Tanggamus regency by studying growth performance EGG, Boerawa grade 1 (BG1), and Boerawa grade 2 (BG2). Survey method was used in this research. Recording for growth performance of 525 heads EGG, 450 heads BG1, and 175 heads BG2 possessed by Karya Makmur III farmer group that was member of the VBC. Variables observed were body weight and body measurements at birth, weaning, and yearling. Data was analysed by analysis for variance of Completely Randomized Design for one way lay out. Difference of mean were analysed by Duncant’s Multiple Range Test. The average of birth weight of EGG (2,79±0,66 kg) were lower than that of BG1 (3,22±0,64 kg), however that of BG1 were not different with BG2 (3,02±0,89 kg). The average of weaning weight of EGG (18,28±0,053 kg) were lower than that of BG1 (19,89±5,72 kg) however that of BG1 were not different with that of BG 2 (19,67±1,54 kg). The average of yearling weight of EGG (39,89±7,26 kg) were lower than that of BG1 however that of BG1(43,49±6,15 kg) were not different with BG2 (42,27±2,12 kg). The absolute preweaning and postweaning average daily gain (ADG) of EGG, BG1, and BG2 were not different. Relative preweaning ADG of EGG (7,95±0,69%) were higher (P&amp;lt;0.05) than that of BG1 (3,57±0,14%) and BG2 (4,77±0,64%) however that of BG1 were not different with BG2. Relative postweaning ADG of EGG (0,60±1,31%) were higher than that of BG1 (0,37±0,01%) and BG2 (0,43±0,07%). Average of postweaning ADG of BG1 and BG2 were different (P&amp;lt;0.05). Its conclusion that growth performance of BG2 have not optimum.&lt;/p&gt;

Performans Pertumbuhan Kambing Boerawa di Village Breeding Centre, Desa Dadapan, Kecamatan Sumberejo, Kabupaten Tanggamus, Provinsi Lampung

&lt;p&gt;The objective of research were to evaluate grading up program of Boer buck and Ettawa grade goat (EGG) doe at Village Breeding Centre (VBC) Dadapan village, Sumberejo subdistrict, Tanggamus regency by studying growth performance EGG, Boerawa grade 1 (BG1), and Boerawa grade 2 (BG2). Survey method was used in this research. Recording for growth performance of 525 heads EGG, 450 heads BG1, and 175 heads BG2 possessed by Karya Makmur III farmer group that was member of the VBC. Variables observed were body weight and body measurements at birth, weaning, and yearling. Data was analysed by analysis for variance of Completely Randomized Design for one way lay out. Difference of mean were analysed by Duncant’s Multiple Range Test. The average of birth weight of EGG (2,79±0,66 kg) were lower than that of BG1 (3,22±0,64 kg), however that of BG1 were not different with BG2 (3,02±0,89 kg). The average of weaning weight of EGG (18,28±0,053 kg) were lower than that of BG1 (19,89±5,72 kg) however that of BG1 were not different with that of BG 2 (19,67±1,54 kg). The average of yearling weight of EGG (39,89±7,26 kg) were lower than that of BG1 however that of BG1(43,49±6,15 kg) were not different with BG2 (42,27±2,12 kg). The absolute preweaning and postweaning average daily gain (ADG) of EGG, BG1, and BG2 were not different. Relative preweaning ADG of EGG (7,95±0,69%) were higher (P&amp;lt;0.05) than that of BG1 (3,57±0,14%) and BG2 (4,77±0,64%) however that of BG1 were not different with BG2. Relative postweaning ADG of EGG (0,60±1,31%) were higher than that of BG1 (0,37±0,01%) and BG2 (0,43±0,07%). Average of postweaning ADG of BG1 and BG2 were different (P&amp;lt;0.05). Its conclusion that growth performance of BG2 have not optimum.&lt;/p&gt;

Effect of Non-Genetic Factors on Reproductive and Growth Performance of Abera Sheep under Community Based Breeding Program in SNNPRS Ethiopia

The study was conducted in Sidama Zone, Dara District Southern Ethiopia. The intention was to investigate the effect of non-genetic factors on reproductive and growth performance of Abera sheep in the District. For this study three years (2013-2015) performance data were obtained from Hawassa research center, Dara sub-site. Study identified age at first lambing (AFL) and lambing interval (LI) of the sheep were 9.6 and 12.9 months, respectively; while annual reproductive rate and litter size of the ewes were 1.9 and 1.5 heads. Average birth weight, weaning weight and 6 month weight of Abera sheep were 2.8, 12.3 and 18.5 kg, respectively; while pre and post weaning average daily weight gains were 106 and 40 g/day, respectively. Birth type, sex and year had significant (p<0.05) effect on birth weight (BWT), weaning weight (WWT) and six-months weight; whereas season and parity had significant (P<0.05) effect on BWT and WWT only. Sex and birth type had significant (p<0.01) effect on pre-weaning average daily gain whereas year, season and parity had significant effect on both pre and post-weaning average daily gain. There was within breed variability in growth traits, which were significantly influenced by non-genetic factors like birth type, sex, year, season and parity. Selection for further improvement to achieve higher lamb crop with superior growth performance should be prioritized as within population variability is raw material for improvement through selection. Molecular characterization should also be carried out to identify uniqueness of Abera sheep.

Evaluation of Crossbreeding of Australian Superfine Merinos with Gansu Alpine Finewool Sheep to Improve Wool Characteristics.

Crossbreeding of Australian Superfine Merinos (ASMs) with Gansu Alpine Finewool (GAF) sheep and an evaluation of the potential benefits of this genetic cross has not been previously conducted. 13 ASMs were crossbred with GAF sheep over a five year period with backcrossing designed to assess heterosis. Data from 11,178 lambs sired by 189 rams were used in the study. Genotype, birth year, birth type, dam age, sex and/or management group, and record age were fitted as fixed effects and within-genotype sire fitted as a random effect. Crossbreeds of 1/2 ASM expressed the most desirable effects for improving average fiber diameter (AFD), clean fleece weight (CFW), yield, coefficient of variation of AFD (CVAFD), yearling staple length (YSL) to AFD ratio (YSL/AFD), and CFW to metabolic yearling bodyweight (YWT0.75) ratio (CFW/YWT0.75) but showed the least post-weaning average daily gain (powADG) and YWT. Genotype of backcrossing with 1/4 ASM obtained moderate improvements in AFD, CFW, CVAFD, and YSL/AFD but the highest YSL, WWT, and prwADG. Except for yield (-1.42%) and CFW/YWT0.75 (-1%), heterosis estimates were generally low and positive, and ranged from 0.1% for CVAFD to 4% for powADG, which indicates the potential to improve relevant traits through exploiting heterosis to a varying extent. The ASMs sampled in this study were found to be superior to GAFs for AFD, CFW, yield, and CVAFD by 19.82%, 11.68%, 14.47%, and 6.99%, respectively, but inferior for YSL, PowADG, and YWT by 4.36%, 50.97%, and 16.93%, respectively. ASMs also appeared to be more efficient than GAFs in clean wool production (25.34%) and staple length growth (16.17%). The results of our study strongly suggest that an infusion of ASM genes via crossbreeding is an effective and appropriate approach to improve wool microns and wool production from GAF sheep, and we make recommendations to tackle the undesirable traits of YWT and YSL from ASM introduction.

Genetic analysis of post-weaning growth traits of Thalli sheep under tropical conditions

Present investigation was carried out to study the influence of genetic and non-genetic factors affecting post-weaning performance traits in Thalli sheep. Data on post-weaning growth of Thalli sheep maintained at Livestock Experiment Station, Rakh Ghulaman, District Bhakkar-Punjab, Pakistan during 1977-2003 were subjected to genetic analysis. The average values for weight at 180 and 270 days of age, yearling weight and post-weaning average daily gain were 22.37 ± 4.21, 25.96 ± 4.90 and 28.93 ± 5.20 kg and 28 ± 0.01 g/day, respectively. Weight at 180, 270 and 365 days of age and post-weaning average daily gain were significantly affected by year of birth, sex, type of birth and weaning weight (covariable) whereas season of birth was a significant source of variation for 180 and 270 days of age. The heritability estimates for 180 and 270 days, yearling weight and post-weaning average daily gain were 0.07 ± 0.02, 0.08 ± 0.02, 0.07 ± 0.02 and 0.07 ± 0.02, respectively.

Effects of milk replacer and starter diet provided as creep feed for suckling pigs on pre- and post-weaning growth.

This study was aimed at investigating the long-term effects of provision of liquid milk replacer (MR) and solid starter diet (SD) during lactation on post-weaning (PW) growth of pigs. In experiment 1, 33 cross-bred litters were allotted to four treatments: no supplement (CON), MR ad libitum, SD ad libitum and 100 g SD/litter/day from lactation day 4 through weaning at day 21 during late fall. In experiment 2, 40 litters received MR or none in July. PW pigs received commercial diets to marketing. In experiment 1, weaning weight (WW), pre-weaning average daily gain (ADG) and mortality (2.4%) were not influenced by creep-feeding MR or SD. ADG was greater (P < 0.05) in the MR group versus CON during days 21-54, but did not differ across the treatments during days 54-162. In experiment 2, ADG during lactation and WW were greater in the MR group versus CON, with mortality lower in the former (5.6 vs. 10.3%). However, PW ADG to day 175 did not differ between the two groups. Results suggest that creep-feeding MR or SD has no effect on PW growth. However, it remains possible that MR reduces PW mortality during the hot season.

Korelasi Genetik Pada Sifat Pertumbuhan Sapi Aceh di Kecamatan Indrapuri Provinsi Aceh

(The genetic correlation of growth traits in Aceh cattle at indrapuri district Aceh Province)ABSTRACT. This research was conducted to estimate genetic correlation of growth traits on Aceh cattle including birth weight (BW), weaning weight (WW), yearling weight (YW), and Average Daily Gain (ADG). The research was done at Indrapuri Breeding and Forage Centre (IBFC) of Aceh cattle from March 2013 to April 2013. The materials of this research consist of growth records from 2010 to 2012. The genetic correlation was analyzed by variance and covariance. The results indicated that the lowest standard error (SE) value of heritability showed on birth weight 0.15+0.13. Most of genetic correlation value on growth traits was positive and high categorized ( 0.50). The lowest SE value showed on correlation between birth weight and pre-weaning ADG (0.55+0.54), birth weight and post-weaning ADG (0,63+0,62), pre-weaning ADG and post-weaning ADG (0.71+0.33), pos-weaning ADG and weight/age or W/A (0.72+0.33) then final weight and W/A (0.94+0.69). It could be concluded that most of genetic correlation value on Aceh cattle growth traits were positive and high therefore the selection based on growth traits can be done for increasing performance in Aceh cattle.

English

&nbsp; The present study was carried out to determine non-genetics effects on the growth performance (birth, weaning, one year weight and weight gains) of Horro cattle and their crosses (Friesian-Horro (FH) and Jersey-Horro (JH)) at Bako Agricultural Research center. The data used in the study included weight records of animals born between 1980 and 2008. Least squares means were analyzed using General Linear Model (GLM) of Statistical Analyses System (SAS). Apart from Breed effects, sex, year of birth and parity were the main non genetic effects that influenced birth weight (BW), weaning weight (WW), one year weight (YW), pre-weaning average daily gain (DG) and post-weaning average daily gain (PDG). The overall mean of birth, weaning and one year weight and pre-weaning and post-weaning average daily gains of Horro and their crosses were 19.6&plusmn;0.16 kg, 43.8 &plusmn;8.5 kg and 84.8&plusmn;21 kg, 407.4&plusmn;20.6 g and 263.7&plusmn;54.3 g, respectively. The least squares means birth weight, weaning weight and one year were: 18.34&plusmn;0.14 kg, 39.8&plusmn;0.39 kg and 70.5&plusmn;1.14 kg for Horro, 22.13&plusmn;0.14 kg, 47.5&plusmn;0.38 kg and 94.7&plusmn;1.14 kg for Friesian-Horro and 19.1&plusmn;0.19 kg, 42.9&plusmn;0.5and kg, 85.5&plusmn;1.5 kg for Jersey-Horro breeds, respectively. From the results suggests that birth weight of the calves doesn&rsquo;t affect the weaning weight and the subsequence growth performance. This could point to an opportunity for much improved weaning and one year weight by improving the management practices of calves. The higher growth performance observed for the crossbred calves in comparison with the purebred Horro (Bos indicus) cattle. &nbsp; Key words:&nbsp;Crosses, fixed, growth, Horro, non genetic, traits.

Factors affecting post-weaning average daily gain and Kleiber ratios in Malpura sheep

The objective of this study was to determine effect of environmental factors on estimates of post-weaning growth traits. Study suggested that as the age advances growth rate and feed conversion efficiency declines in Malpura sheep. Hence, for higher economic gain selection should be made at earlier age, preferably at 6 month. Rearing male lambs can be more profitable as they achieved higher growth and better feed conversion efficiency. For unbiased estimates of breeding values, correction factors for significant non-genetic factors must be incorporated.

GANHO DE PESO PRÉ E PÓS-DESMAME NO DESEMPENHO REPRODUTIVO DE NOVILHAS DE CORTE AOS QUATORZE MESES DE IDADE

The objective of this experiment was to study the development and reproductive performance of sixty-six Charolais crossbred beef heifers bred at fourteen months of age, classified in four groups according to pre and postweaning average daily weight gain (ADG): AA= heifers that showed ADG > .54 kg and .73 kg, respectively; AB= heifers that showed ADG > .54 kg and .73 kg, respectively; BB= heifers that showed ADG < .54 kg and < .73 kg, respectively. Weight at the beginning and end of the breeding period, and the reproductive performance were influenced by ADG of the heifers during pre and postweaning phase. AA heifers showed better development in relation to the other groups, without difference between AB and BA. The AA group was superior to the others except for the reproductive performance of the group AB. Heifers that became cyclical showed higher development during the growing phase and mating period than acyclic heifers. Reproductive performance of heifers was positively correlated with weight and body condition at beginning and end of the mating period. Greater weight during pre and post-weaning improve the reproductive performance of beef heifers. KEYWORDS: body condition; Charolais; estrus; pregnancy; weight at mating.