Parity Of Dam Research Articles

Dam parity and calf sex affect maternal and neonatal behaviors during the first week postpartum in stabled Maghrebi dairy camels

Currently, a trend toward the commercialization of dromedary milk associated with recent intensive rearing systems has starting worldwide which impose constraints on animals affecting their behavioral repertoires and welfare status. The aim of this study was to investigate the effects of dam parity and calf sex on parturition, neonatal, and maternal behaviors in stabled Maghrebi dairy camels (Camelus dromedarius). Thirty-six (primiparas N = 10; multiparas N = 26) periparturient females were kept under video surveillance using a digital IR camera and 24-h sessions were chosen to assess calving, maternal, and neonatal behaviors in calving pens. Duration of restlessness, process of giving birth, and expulsion of fetal membranes were assessed. After first suckling, dams and their calves were moved into an individual enclosure to assess maternal behavior at 12 h, 24 h, 48 h, 72 h, and 7d postpartum. Behavior was assessed using a camcorder for 30 min after 1 h of young separation in an adjacent enclosure. Results showed an effect of parity on the duration of the birth process which was longer for primiparous than multiparous camels (P = 0.034). During this stage, primiparous females tended to raise their tails more often (P = 0.054) and spent more time standing (P = 0.001) than multiparous camels. Neonatal behavior was affected by calf sex. Female newborns took less time to raise their heads (P = 0.041) and to stand up (P = 0.048) for the first time and were the earliest to suckle their dams (P = 0.032). Multiparous dams stood up sooner (P = 0.019) after calving and suckled their calves earlier (P = 0.043) than primiparous dams. They emitted more bleats and exhibited more sniffing during the first week postpartum than primiparas. During the first postpartum week, both primiparas and multiparas showed a decrease in the total number of bleats (P < 0.001), low-pitch bleats (P < 0.001), and high-pitch bleats (P < 0.001), in sniffing frequency (P < 0.001) and sniffing duration (P < 0.001). This is the first study to describe in detail the calving, maternal, and neonatal behaviors of dromedary camels and to show the influence of parity and calf sex. Maternal care toward the newborn calf exhibited by a high level of bleating and sniffing activities in the first 2 days suggest that they play an important role in the establishment of mother–young relationship.

EVALUATION OF THE REPRODUCTIVE PROBLEMS OF FRIESIANS, BUNAJI AND CROSSED COWS IN A SUBTROPICAL ENVIRONMENT

Herd health fertility records of 248 cows comprising 103 Friesians, 84 Bunaji and 61 Crossbreeds in Vom from 1992-1999 were utilized to study the incidence of reproductive problems. The overall incidence of various reproductive problems was 54.4% and this was more frequent (P&lt;0.001) in crossbred cows (72.6%) than in Friesians, (59.9%) and in Bunaji (32.7%). Second Calvers (67.1%) were more susceptible (P&lt;0.01) to reproductive problems than heifers (56.0%) and mature cows (45.3%). The incidence of still birth (8.10%) and relative infertility (8.2%), were influenced by genotype (P&lt;0.05); similarly genotypic differences (P&lt;0.001) were observed in the incidence of retained placenta (7.4%). Abortion (5.6%), dystocia (12.2%) and repeat breeding (12.5%) were uniformly distributed among genotypes. Parity of dams had marked influence (P&lt;0.001) on dystocia, still birth and retained placenta. Significant differences (P&lt;0.0l) were also observed on the incidence of relative infertility, but the rate of dystocia (P&lt;0.01), abortion and repeat breeding (P&lt;0.001) varied with the years. The results emphasize the need for greater management intervention to reduce the incidence of reproductive problems in sub tropical cattle herds.

Risk factor analysis for beef calves requiring assisted vaginal delivery in Great Britain.

Dystocia has serious consequences for both mother and offspring. This study therefore aimed to identify risk factors for dystocia in vaginally delivered spring born beef calves in Great Britain (GB). Information on calving assistance, calf sex, birthweight, breed, twinning, dam parity and body condition score (BCS) was collected from 1131 calves across 84 GB farms. Variables were modelled against calving assistance as a binary response variable. Twins (Odds Ratio [OR] = 5.45), Charolais calves (OR = 3.24), calves from primiparous dams (OR = 5.75) and male calves (OR = 1.75) were at significantly increased risk of requiring calving assistance across all models. Calves born to cows classed as thin (BCS < 2.5/5) were identified in the univariate analysis and in one of the multivariate models (OR = 1.92) as having an increased likelihood of dystocia. Most beef herds have limited scope to manage cows on the basis of fetal gender and number. However, calf breed, dam body condition and management of primiparous dams can be manipulated to reduce the risk of dystocia and improve supervision. Poor body condition is a novel risk factor for dystocia in beef cows and worthy of further investigation.

Abstracts from the Proceedings of the 33rd Biennial Conference of the Australian Association of Animal Sciences

Encapsulated calcium butyrate (ECAB, ButiPEARL™, Kemin Industries, Inc. Des Moines, Iowa) is a novel and innovative feed technology developed to release butyrate continuously and slowly in the gastrointestinal tract of animals. Butyrate promotes rapid growth and development of rumen papillae for a better absorption of digested nutrients that enables dairy calves to transition smoothly from liquid milk to concentrates with minimal metabolic disorders (Pereira et al. 2017; Eckert et al. 2015; Ferreira & Bittar, 2011). This study investigated the effect of supplementing dairy heifer calves with ButiPEARL™ on average daily weight gain, liveweight and body conformation traits. The study was conducted using forty-eight newly born heifer calves (7 ± 0.4 days old; average liveweight 39.3 ± 5.3 kg) comprising purebred and crossbred Friesians, Jersey and Swedish Red. Calves were kept under the same pasture-based management system and utilised in a complete randomised experimental design for eleven weeks. The treatment groups included the Control (no supplementation), Low (4 kg/t) and High (6 kg/t) doses of ButiPEARL™. Feed intake, liveweight, average daily weight gain and body conformation parameters were subjected to a repeated measures general mixed model (proc mixed) analysis in SAS. Treatment diet, calf breed, dam parity, week of measurement and their first-order interactions fitted as fixed effects, while dam age was fitted as a random effect and all the initial body weight and conformation measurements fitted as covariates. Dose affected liveweight, average daily weight gain, chest girth, withers height, body length and body condition score (P < 0.05). The Low dose resulted in the highest average daily weight gain (0.83 ± 0.03 kg/day), heaviest liveweight (72.08 ± 1.6 kg), widest chest girth (95.94 ± 0.7 cm), longest body length (82.92 ± 0.6 cm) and best body condition score (1.99 ± 0.1; Table 1). Calves assigned to Control and High doses had similar liveweights (65.37 ± 1.4 kg vs 65.74 ± 1.5 kg), average daily weight gain (0.71 ± 0.0 kg vs 0.74 ± 0.0 kg) and chest girth (93.35 ± 0.7 cm vs 92.91 ± 0.7 cm; Table 1). These findings suggest that calf starter rations containing 4 kg/t ButiPEARLTM will improve overall liveweight and body conformation traits of newborn calves in a pasture-based system. Practical implications of supplementing neonatal dairy calves with ECAB is the potential to wean calves early and reduce age at first calving, which has been shown to result in improved lifetime performance. References Eckert E, Brown H, Leslie K, DeVries T, Steele M (2015) Journal of Dairy Science 98, 6315-6326. Ferreira L, Bittar C (2011) Animal 5, 239-245. Pereira GR, Barcellos JOJ, Sessim AG, Tarouco JU, Feijo FD, Neto JB, Prates ER, Canozzi MEA (2017) Revista Brasileira de Zootecnia. 46, 413-420.

Influence of weaning strategy on behavior, humoral indicators of stress, growth, and carcass characteristics.

Weaning is one of the most stressful events a calf experiences in our current beef production system. Its effects may include reduced feed intake, increased activity, slower growth, and increased susceptibility to disease. This study was designed to evaluate weaning after a 7-d placement of nose flaps at 7 mo (N, n = 40) and delaying weaning by 49 d relative to 7-mo weaning (D, n = 39) as alternatives to the industry standard; abrupt weaning at 7 mo of age (A, n = 39). The 4-yr trial utilized Angus and Angus X Senepol steer calves. Calves were randomly assigned to weaning strategy after being stratified by dam parity (heifer/cow), hair coat phenotype (normal/slick), and body weight. Behavioral observations were made on five steers per strategy group per year over the weeks surrounding weaning. Activity levels were determined by accelerometers worn on neck collars. Blood samples were obtained from the observed cattle during the last 2 yr to determine haptoglobin and cortisol concentration. Once weaned, the steers were followed through finishing and carcass characteristics obtained at harvest. Twelve of 38 steers in the N group had sores in their nostrils from the nose flaps when the flaps were removed at weaning of A/N (237 ± 3 d of age). The A and D calves were more active than N calves in the first 2 to 3 d after weaning but settled down to similar activity levels to N by the day 4. The A and D groups were more vocal than N during the same time frame. Cortisol and haptoglobin remained within normal reference ranges. Average daily body weight gain (ADG) was greater for D than A, who in turn had greater ADG than N during the first 42 d after A and N calves were weaned (0.69, 0.54, and 0.37 kg/d for D, A, and N, respectively; P < 0.01). All treatment groups graded Low Choice at harvest and exhibited similar efficiency of gain during growth and finishing (P > 0.2). Based on ADG during the 42 d after weaning, we recommend delaying weaning when available pasture and cow body condition support this strategy. When conditions do not permit delayed weaning, abrupt weaning may be the next viable option based on animal welfare concerns and increased handling to place and remove the flaps. Nose flaps reduced vocalization at weaning but resulted in less postweaning ADG. Based on our data, we suggest that abrupt weaning under the conditions of this study, is less stressful than we perceive it to be, based on calf behavior.

Influence of inbreeding and some environmental factors on calving intervals in N'Dama cattle of Southwest Nigeria

Records of 4184 N'Dama calves born between 1947 and 1984 at Fashola Stock Farm, Oyo State, Nigeria was used to compute inbreeding coefficient and determine its effects on calving intervals of cows. Only 273 of the 4184 calves (6.53%) were inbred with an average inbreeding coefficient of 9.71%, while five out of 293 sires had inbreeding coefficient of 9.25% and 43 out of 1849 dams had inbreeding coefficient of 9.95%. The inbreeding coefficient for the entire population was 0.63%, respectively 0.70% and 0.58% for male and female calves. The average calving interval was 445.34 ± 2.68 days within the herd while year of birth, parity of dam, age of dam and dam's age at first calving all significantly (P&lt;0.05) impacted calving intervals of cows. Season of birth and inbreeding coefficient of dam did not exert statistical (P&gt;0.05) influence on calving intervals of dams. Although the number of inbred animals in the population is relatively low, however the inbreeding level of these animals is high, which may be attributed to the fact that breeding policy on the farm was not strictly adhered to, and lack of proper and adequate registration system coupled with inconsistent animal identification system on the farm may be responsible for the inbreeding observed in the N'Dama population at Fashola Stock Farm.

Measurement of transfer of colostral passive immunity in dairy calves

Measurement of transfer of colostral passive immunity in dairy calves

222 Effect of genetic line and parity of dam on litter birth weight and weaning weight in swine

Abstract The objective of this study was to evaluate the effects of parity and genetic line of the dam on her offspring and their ability to thrive until weaning. Data were obtained from 17 purebred litters and 72 crossbred litters and the parity of the dam ranged from 1-13. Parities were grouped into the following categories: parity 1, parity 2, parity 3-5, and parity 6+. Entire litters were weighed at birth and weaning (~28 days of age). Litters were grouped into four weight categories based on the time of year they were born: February, April, May, and July 2019. Data were analyzed by using mixed model methods (Proc Mixed, SAS V. 9.4, SAS Inst. Inc. Cary, NC). The birthweight model included fixed effects of parity and genetic line. Birth month was included as a random variable, and number born alive was used as a covariate. Mean litter birth weight was significantly different between parity 1 and parity 3-5 (P=0.001), parity 2 and parity 6+ (P=0.031), and parity 3-5 and parity 6+ (P=&amp;lt; 0.0001). The difference between parity 2 and parity 3-5 approached significance. Birthweight differed between genetic line (&amp;lt; 0.0001): Crossbred litter birthweight was 4.15kg greater than purebred litter birthweight. The weaning weight model included genetic line, parity, and number of pigs after fostering. Birth month was included as a random variable, and age at weaning and birth weight were used as covariates. Weaning weights for parity and genetic line did not differ (P &amp;gt;0.05).

38 Effects of combining nose flap weaning with short-term creep feeding of beef calves on cow and calf performance

Abstract One hundred four Angus calves were ranked by gender, BW, age, and dam parity, and assigned to 1 of 4 pre-weaning treatments: 1) nose flaps for 7-d prior to weaning (NF), 2) traditional weaning (TRAD), 3) traditional weaning and creep feed for 3-wk prior to weaning (TRADC), or 4) nose flaps for 7-d prior to weaning and creep feed for 3-wk prior to weaning (NFC). Cow-calf pairs were housed in dry lot pens on d -28. From d -21 to 0, calves in creep treatments were provided free choice access to creep feed. Nose flaps were placed on d -7, and calves were weaned on d 0. Calves were vaccinated and dewormed on d -21 and 0. There was no difference (P ≥ 0.97) in calf BW on d -28 or -21. During the 7-d period that nose flaps were placed, NFC calves had greater (P ≤ 0.0001) ADG than NF and TRAD calves, and tended to have greater (P ≤ 0.10) ADG than TRADC calves. At weaning on d 0, TRADC and NFC calves tended to have greater BW (P = 0.07) and had greater overall change in BW (P &amp;lt; 0.0001) during the pre-weaning period than TRAD and NF calves. Additionally, there was a greater (P ≤ 0.001) increase in BW of NFC and TRADC cows during the pre-weaning period compared to NF and TRAD cows. From d -21 to 0 there was no differences (P &amp;gt; 0.41) in plasma concentrations for Bovine Viral Diarrhea Virus (BVD). By d 14, the TRADC calves had the greatest plasma concentrations for BVD (P &amp;lt; 0.04). Therefore, providing short-term creep feed prior to placing nose flaps can improve pre-weaning calf and cow performance compared to traditional and nose flap weaning without creep feed supplementation, however, did not improve response to vaccination.

Evaluation of models for estimation of genetic parameters for post-weaning body measurements and their association with yearling weight in Nellore sheep.

The objective of this study was to obtain (co) variance components and genetic parameter estimates for post-weaning body measurements such as body length, height at withers and chest girth recorded at six (SBL, SHW and SHG), nine (NBL, NHW and NHG) and twelve (YBL, YHW and YHG) months of age along with yearling weight (YW) in Nellore sheep maintained at livestock research station, Palamaner, Andhra Pradesh, India and also the association among body measurements with yearling weight was studied. Data on 2,076 Nellore sheep (descended from 75 sires and 522 dams) recorded between 2007 and 2016 (10 years) were utilized in the study. Lambing year, sex of lamb, season of lambing and parity of dam were included in the model as fixed effects and ewe weight was kept as a covariate. Analysis were conducted with six animal models with different combinations of direct and maternal genetic effects using restricted maximum likelihood procedure. Best model for each trait was determined based on Akaike's Information Criterion. Moderate estimates of direct heritability were obtained for the studied traits viz., BL (0.02-0.24), HW (0.31-0.49) and CG (0.08-0.35) and their corresponding maternal heritability estimates were in the range of 0.00-0.07 (BL), 0.13-0.17 (HW) and 0.07-0.13 (CG), respectively. Positive direct genetic and phenotypic correlations among the traits and they ranged from 0.07 (YBL-YW) to 0.99 (SBL-SHG, SHG-YW and NBL-YBL) and 0.01 (SBL-YBL) to 0.99 (NBL-NHG), respectively. Further, the genetic correlations among all the body measurements and yearling weight were positive and ranged from 0.07 (YW and YBL) to 0.99 (YW and SHG). Strong association of chest girth at six months with yearling weight. Further, it is indicated that moderate improvement of post-weaning body measurements in Nellore sheep would be possible through selection.

THE IMPACT OF MANAGEMENT SYSTEMS ON CALVES PERFORMANCE

Records of 3691 growing Holstein Friesian calves, from birth up to weaning (born in a period from 2013 to 2019), belonging to commercial farm named El-Baiomy dairy farm located in Gamasa-Dakahlia Province- Egypt were used in this study. Data collected included management factors such as dam effect (dry period, parity, calving interval and previous milk production) and calves management (Housing system, suckling system, season and gender) and their effects on calves' performance (birth weight (kg), weaning weight (kg), weaning age (day) and daily gain (kg/day)). There were no significant effects in dry period length, parity, calving interval and previous milk production of dam on calf's performance. The lowest birth weight found to be in first parity cows (31.63 kg), while the heaviest one was found to be in third parity cows (33.00 kg). The lowest calves birth weight (30.40kg) was produced by high yielder cows (>11 ton). While it was been 31.71kg for calves belonging to cows with low (< 9 ton) milk production. There was significant effect (P ≤ 0.05) of housing system, suckling system and seasons of calving on weaning age and daily gain of calves. The lowest birth weight was been in winter (31.34 kg) however the heaviest one was been in winter (93.88 kg). The heaviest birth weight was been in male (32.93 kg) but female was 31.63 kg only. On the other hand weaning age found to be 81.31 and 79.14 days in female and male respectively. In addition, a supplementary study has been made to explain management systems of calves raised in some Egyptian villages using field survey. Data of 267 questionnaires (3458 Animals) have been recorded and analyzed to study calf's management systems in different farms located in Nile delta.

THE IMPACT OF MANAGEMENT SYSTEMS ON CALVES PERFORMANCE

Records of 3691 growing Holstein Friesian calves, from birth up to weaning (born in a period from 2013 to 2019), belonging to commercial farm named El-Baiomy dairy farm located in Gamasa-Dakahlia Province- Egypt were used in this study. Data collected included management factors such as dam effect (dry period, parity, calving interval and previous milk production) and calves management (Housing system, suckling system, season and gender) and their effects on calves' performance (birth weight (kg), weaning weight (kg), weaning age (day) and daily gain (kg/day)). There were no significant effects in dry period length, parity, calving interval and previous milk production of dam on calf's performance. The lowest birth weight found to be in first parity cows (31.63 kg), while the heaviest one was found to be in third parity cows (33.00 kg). The lowest calves birth weight (30.40kg) was produced by high yielder cows (>11 ton). While it was been 31.71kg for calves belonging to cows with low (< 9 ton) milk production. There was significant effect (P ≤ 0.05) of housing system, suckling system and seasons of calving on weaning age and daily gain of calves. The lowest birth weight was been in winter (31.34 kg) however the heaviest one was been in winter (93.88 kg). The heaviest birth weight was been in male (32.93 kg) but female was 31.63 kg only. On the other hand weaning age found to be 81.31 and 79.14 days in female and male respectively. In addition, a supplementary study has been made to explain management systems of calves raised in some Egyptian villages using field survey. Data of 267 questionnaires (3458 Animals) have been recorded and analyzed to study calf's management systems in different farms located in Nile delta.

10.4314/sajas.v40i5.65301

Live weight data from 590 Murrah buffalo calves (140 male and 450 female calves) maintained at the Central Cattle Breeding Farm, Alamadhi, Tamil Nadu, India, born in the period between 1990 and 2004 were used for this study. Data were analysed using least-squares procedures. The adjusted birth weights of male and female calves were 33.0 ± 0.49 and 31.9 ± 0.27 kg, respectively, with an overall value of 32.4 ± 0.30 kg. The mean body weight at three, six, nine and 12 months of age pooled over periods, season and sex were 62.0 ± 0.65, 87.9 ± 0.95, 112.4 ± 1.23 and 134.16 ± 1.41 kg, respectively. Period of calving influenced the weight significantly at birth, three and six months of ages only. The effect of dam parity on body weight at different ages was highly significant. The calves born during the dam’s second parity were generally heavier than those born in other parities. Generally, males had a higher body weight than females at all age groups. All the growth traits showed medium heritability (direct) estimates, which ranged between 0.12 ± 0.01 and 0.22 ± 0.16. The genetic correlations were all medium to high and positive. The genetic parameter estimates indicated that the six months weight can be used as a selection tool for genetic improvement of growth traits considering its high heritability and positive genetic correlations with succeeding growth traits.

A large-scale study on the effect of age at first calving, dam parity, and birth and calving month on first-lactation milk yield in Holstein Friesian dairy cattle

Milk yield during first lactation is an important economical trait. Age at first calving (AFC) is considered an important predictor of subsequent milk yield. In addition, both season of birth, as well as season of calving, have been shown to influence milk production, with conflicting results. Finally, higher parity of the dam has been associated with a lower performance of the offspring. The aim of the present study was to assess the effect of the above-mentioned factors based on a large-scale study and to rank the most important determinants for first-lactation milk yield. Data on 3,810,678 Holstein Friesian heifers, born in Belgium and the Netherlands between 2000 and 2015, were provided by Cooperative CRV and CRV BV (Arnhem, the Netherlands) and consisted of birth dates, calving dates, and first-lactation productions. In addition, herd, sire, and dam information was provided. Linear regression models were built with herd-calving year and sire as random effects and 305-d energy-corrected milk (ECM) yield during first lactation as outcome variable. Birth month, calving month, parity of the dam, and AFC were included as fixed effects in the model and a dominance analysis was performed to rank the associated factors according to importance. Results revealed AFC to be the most important factor (R2 = 0.047), with an increase in ECM up to an age of 33 mo. Calving month was a more important predictor than birth month (R2 = 0.010 vs. R2 = 0.002, respectively), with the highest first-lactation production in heifers calving in October to December, and the lowest in heifers calving in June and July. Birth month had a limited effect on first-lactation milk yield (R2 = 0.002), potentially masked by rearing strategies during early life. Finally, parity of the dam ≥3 was associated with a reduced ECM of the offspring (R2 = 0.002). In conclusion, our results show AFC to be an important determinant of milk yield during first lactation. In addition, seasonal patterns in milk production are seen, which should be further explored to identify the underlying mechanism.

Effects of the Administration of a Non-specific Immune Stimulant Around Transportation on Health and Performance of Jersey and Jersey-Cross Heifer Calves During the Rearing Period: Randomized Clinical Trial.

Our objective was to evaluate the effects of a non-specific immune stimulant (IS) administered around transportation on health scores (HS), average daily gain (ADG), disease treatment and mortality of Jersey and Jersey-cross calves during the rearing period. Newborn calves (4 d ± 1) were randomly allocated to receive either 1 mL of saline (CON; n = 438), 1 mL of IS before transport (BTIS; n = 431), or 1 mL of IS immediately after transport (ATIS; n = 436). Calves were health scored weekly for 3 weeks after transport. The data were analyzed using multivariable linear mixed models and multivariable logistic regression models. Kaplan-Meier survival analysis was performed for time to event analysis. Treatment, birth weight, breed, site of birth, serum total solids, dam parity, season of enrollment, and metaphylaxis were offered to models. Differences in respiratory and fecal HS, and ADG between treatment groups were not statistically significant. A total of 196 (15.0%) calves were treated at least once for any disease and 52 calves were treated multiple times. The proportion of calves treated for respiratory disease and/or diarrhea were 14.4, 14.4, and 16.2% for BTIS, ATIS and CON groups, respectively. Although the differences in the likelihood of treatment for both respiratory disease and/or diarrhea during the first 9 weeks of life was not statistically different between groups, we observed that more calves in the control group received disease treatments around 15 days of age compared with calves that received IS. The likelihood of treatment for respiratory diseases alone during the first 30 days of life was smaller in the calves that received IS before transportation when compared to the control group. Only 18 (1.4%) calves died within the study period. The calf mortality likelihood was not statistically different between study groups; however, fewer calves in the IS groups died when compared to CON. In conclusion, the use of IS around transportation did not influence weekly HS, ADG, and the number of disease treatments during the rearing period, but administering IS before transportation resulted in fewer treatments of respiratory diseases during the first 30 days post-transport and marginally lower mortality rates during the rearing period.

Carcass and efficiency metrics of beef cattle differ by whether the calf was born in a dairy or a beef herd.

Beef originates from the progeny of either dairy or beef dams. The objective of the present study was to identify contributing factors to the differences in the carcass merit of progeny from both dam types. This goal was achieved using slaughter records from 16,414 bucket-reared dairy animals (DXD), 5,407 bucket-reared dairy-beef animals (BXD), 42,102 suckle-reared animals from a beef × dairy F1 cross dam (BXF1), and 93,737 suckle-reared animals from a beef × beef cow (BXB). Linear mixed models were used to quantify the least squares means for carcass characteristics in the various progeny genotypes. Nuisance fixed effects adjusted for in the models were: animal heterosis and recombination loss, dam parity, age at slaughter, and contemporary group; age at slaughter was replaced as an independent variable with both carcass weight and carcass fat score where the dependent variable was age at slaughter. In a follow-up analysis, models were re-analyzed where the genetic merit of the sire was adjusted for; a further analysis set the genetic merit of the dam for the dependent variable to be identical for both the dairy and beef dams. The final analysis adjusted to a common sire and dam genetic merit facilitating the estimation of just differences in early-life rearing strategies. Irrespective of the genetic merit of the sire and dam, animals originating from beef herds had heavier and more conformed carcasses. BXB animals had a 67 kg heavier carcass, with a conformation score (scale 1 [poor] to 15 [excellent]) of 5 units greater compared with DXD animals. When the genetic merit of all dams was set to be equal, BXB animals were heavier and better conformed than BXD animals. When the genetic merit for both the sire and dam were set to be equal, carcasses of the BXB animals were 15 kg heavier, with a 0.69 unit superior conformation score compared with the DXD animals; this difference is due to early life experiences. In conclusion, the majority of the inferiority in carcass metrics of calves from dairy herds compared with beef herds is due to differences in the genetic merit of the parents. Nevertheless, even after adjusting the parents to the same genetic merit, progeny from dairy herds were still inferior to their contemporaries born in beef herds, due most likely to the persistence of early life experiences.

Genetic Improvement of Some Productive Traits in Zaraibi Goats

The objective of this study was to evaluate the genetic improvement in Zaraibi goats herd raised on El-serw research station located in the north eastern part of Nile Delta, Egypt. The station belongs to Animal Production Research Institute (APRI). Some body weights at different ages were included in genetic and environmental trends. These weights were 4-month weight (4M), 6-month weight (6M), and 12-month weight (12M). Data and pedigree information were collected from 1988 until 2018. The least square means of body weights at 4M, 6M and 12M were 12.14±0.02, 15.49±0.02 and 24.08±0.04 kg, respectively. Year of birth, season, gender of kid, parity of dam and type of birth significantly (P<0.01) affect growth traits. Genetic parameters were estimated using a multi-trait animal model program (MTDFREML). The same previous fixed effects were included in this analysis regarding the animal as random effects. The heritability of the studied body weights tend to increase as age increases. That is inversely matched with the environmental proportion of total variance which was found to be 0.72, 0.66 and 0.62 for M4, M6 and M12, respectively. The heritability value was estimated as 0.28 for 4M. Genetic trends were obtained as the regression of the predicted breeding values on years of birth and Environmental trends were obtained as the regression of year constants on years of birth. The annual genetic change trends were positive and significant for 4M, 6M and 12M (0.091, 0.121 and 0.158 kg/year, respectively) and the annual phenotypic change trends were (0.020, 0.045, 0.117 kg/year, respectively). Genetic trends for M12 trait were higher than those for other traits in this study. Genetic and environment correlations between 4 month body weight and other growth traits were positive. Negative environmental trends indicates poor management system for the flock during studied period. Weight at 12 months of age has the highest heritability in studied body weights and suggested to be selection criteria to improve yearling weight for Zaraibi goat.

Etio-Epidemiological Studies on Diarrhoea in Cattle and Buffalo Calves

Calf diarrhoea is the most commonly encountered disease syndrome and significant cause of economic losses in dairy industry. Present investigation was undertaken to find out the prevalence of causative agents of diarrhoea in the bovine calves for a period of one year. The effect of age, sex, season and parity of dam was also studied. E. coli was the major organism (86.00 %) observed in the faecal samples of the diarrhoeic calves followed by rotavirus, Eimeria spp. and Amphistomes (15.00 % each); Toxocara spp. (12.00 %); Strongyles (9.00 %); Cryptosporidium spp. (6.00 %); Trichuris spp. (5.00 %); and Salmonella spp. and Strongyloides spp. (3.00 % each). The prevalence of rotavirus, Cryptosporidium spp. and Eimeria spp. was found significantly higher in buffalo calves and crossbred calves than cow calves and Gir / local non-descript calves, respectively. The prevalence of Toxocara spp., Amphistomes and Strongyles in diarrhoeic buffalo calves was significantly higher than cow calves. Highest prevalence of E. coli and rotavirus was observed in faecal samples of diarrhoeic calves of 0-15 days age group. Rotavirus was not detected in faecal samples of diarrhoeic calves above 60 days age. The susceptibility of bovine calves for E. coli and rotavirus was found decreased with the advancement of the age. The prevalence of Salmonella spp. in diarrhoeic faecal samples of bovine calves was observed only in 16-60 days age whereas Cryptosporidium spp. was found only in 0-30 days age. The most of the parasitic infestations were observed after 30 days of age in calves. The calves of both sexes were equally susceptible to different causative agents of diarrhoea. The prevalence of E. coli and most of the helminth ova in the faecal samples of diarrhoeic calves was found maximum during rainy season whereas the rotavirus was observed mostly during winter season. The prevalence of E. coli, Salmonella spp., rotavirus and Cryptosporidium spp. was found highest in the faecal samples of the diarrhoeic calves of first or second parity dams.

Relation between non-infectious factors and neonatal calf health status in dairy herd.

The aim of this research was to determine some non-infectious factors (sex of calf, calf birth weight, calving season and dam parity and dam body condition score at dry and calving) that can under control by breeders affecting calf health status (CHS) in neonatal period. A total of 517 calves (from delivery of calf until 28days) and their dams (at dry and calving) were assessed according to study criteria. Relationship between CHS and dam parity (DP), body condition score at calving (BCSC ), body condition score at dry (BCSD ), sex of calf (SC), calf birth weight (CBW), and calving season (CS) was examined and connection between CHS and BCSD , CS, and CBW was found important. Also, influences of DP, SC BCSC , and BCSD on CBW were examined and while effects of DP and SC on CBW were found important, effects of others were not. These results show that relation between CHS and CBW, CS, and BCSD is important and CHS is higher in female calves or calves born to multiparous dams. As a conclusion, it can be said that planning the herd management practices according to these results will be beneficial for the healthier completion of the neonatal period.

The Growth Performance of Black Bengal goat in Village Condition of Bangladesh

The study was conducted about the growth performance of Black Bengal goat in village condition at Savar Upazila under the Dhaka District from June/2017 to April/2018. Least-squares means for body weights at birth, 3, 6, 9 and 12 months of ages were 1.10, 5.02, 8.41, 10.41 and 12.42 kg respectively. Sex has highly significant (p < 0.01) effect on the body weight at 3 months (5.22 ± 0.04 and 4.77 ± 0.04 kg), 6 months of ages (8.74 ± 0.04 and 7.96 ± 0.04 kg) and sex has significant (p < 0.05) effect on the body weight at 9 months (10.66 ± 0.09 and 10.10 ± 0.10 kg) and 12 months (12.88 ± 0.06 and 11.82 ± 0.07 kg) respectively male and female. Type of birth has highly significant (p < 0.01) effect on body weight at birth, 3, 6, 9 and 12 months. Parity has highly significant (p < 0.01) body weight at 3 months (4.95 ± 0.05, 5.04 ± 0.04 and 5.08 ± 0.05 kg) and 12 months (12.21 ± 0.67, 12.39 ± 0.08 and 12.67 ± 0.07 kg) and significant (p < 0.05) effect at birth weight (0.94 ± 0.01, 0.95 ± 0.01 and 0.97 ± 0.01 kg) and 6 months body weight (8.29 ± 0.06, 8.37 ± 0.05 and 8.54 ± 0.05 kg) respectively at 1st, 2nd and 3rd parity. Season has a highly significant (P < 0.01) effect in birth weight (0.91 ± 0.01, 0.99 ± 0.01 and 0.97 ± 0.01 kg), 3 months (4.87 ± 0.04, 5.22 ± 0.04 and 4.89 ± 0.06 kg), 12 months (12.21 ± 0.06, 12.65 ± 0.07 and 12.30 ± 0.10 kg) and season has significant effect (P < 0.05) at 6 months body weights (8.20 ± 0.04, 8.63 ± 0.05 and 8.23 ± 0.07 kg) respectively in winter, summer and rainy season. It can be concluded that male type of sex, single type kid, third parity of dam and summer season was better.