Effect of body condition score at mating on the reproductive performance of Kivircik sheep under an extensive production system

Influence of body condition score during late pregnancy on the variations of biochemical parameters and lamb stillbirths in Rembi ewes

The transition period in ewes is associated with a lot of changes, such as metabolic disorder due to the mobilization of body reserves, behavior trouble, food intake, and some changes in body condition score (BCS). This knowledge led us to hypothesize the influence of BCS in ewes during late pregnancy on the variations of biochemical parameters and its influence on the survival of lambs. In order to assess how BCS affected changes in biochemical parameters and lamb stillbirth, blood samples were collected in heparin tubes from forty-nine randomly chosen ewes of the Rembi breed that were clinically healthy and at the end of their pregnancies. The results showed that glucose (Glu) and urea values were highly influenced by the BCS (P < 0.001), while cholesterol (CHL) and gamma-glutamyl transferase (GGT) were significantly influenced by the BCS (P 0.05). We also noted a highly significant decrease (P < 0.001) in the concentration of plasma of Glu and CHL in ewes with BCS = 4 compared to those with BCS = 2, recording a negative correlation (Glu and BCS, r =  - 0.52; P = 0.0001) and (CHL and BCS, r =  - 0.36; P = 0.009). In contrary, serum urea values were highly increased in ewes with BCS = 4 compared to those with BCS = 2 with a positive correlation (urea and BCS, r = 0.72; P = 0.001). On the other hand, the highest rate of lamb mortality was recorded in ewes with BCS = 4 compared to those who had a BCS = 2 with a significant difference (P < 0.05). During late pregnancy, poor body condition or obesity of ewes were predisposing factors for metabolic disease and lamb stillbirths, which can cause significant economic losses.

Seasonal Effects on Body Condition and Characteristics of the Estrous Cycle in Captive Asian Elephants (Elephas maximus) in Thailand: A Retrospective Study

The aim of this study was to investigate the effects of season on the body condition score (BCS), the characteristics of the estrous cycle (luteal phase [LPL], follicular phase [FPL], estrous cycle [ECL] lengths, and the start of the luteal phase [SLP] and follicular phase [SFP]), and progesterone levels (baseline and peak) of eight captive Asian elephants (Elephas maximus) in Thailand. From 2014 to 2019, blood samples were collected weekly for serum progesterone enzyme immunoassays (EIAs). Estrous cycles (n = 70), including the luteal and follicular phases, and BCS (n = 70) were recorded. Based on the BCS, the LPL, FPL, and ECL were assigned to the following two groups: normal (BCS = 3.0-4.0, n = 38) and overweight (BCS = 4.5-5.0, n = 32). The findings demonstrated that there was no difference in LPL between the groups. However, in the normal group, the ECL was one week longer (14.9 ± 1.7 vs. 13.9 ± 1.7 weeks; p < 0.05), and the FPL also tended to be one week longer (7.2 ± 1.7 vs. 6.4 ± 1.5 weeks; p = 0.06) than in the overweight group. The mean progesterone level during the rainy, hot, and cool seasons was not statistically different. Based on the yearly averaged BCS from three seasons, the baseline and peak levels of progesterone were classified into the normal (n = 16) and overweight (n = 12) groups. Females with a normal BCS tended to exhibit higher progesterone peak levels (p = 0.08). The majority of peaks appeared during the rainy season (53.57%). The BCS was highest during the hot (4.47) and rainy (4.38) seasons, but not during the cool (4.12) season. The LPL, FPL, and ECL were not affected by the season in which the luteal phase occurred. On the other hand, the rainy season had a significant effect on the SFP, resulting in a longer LPL (p < 0.05) and ECL (p = 0.01); both were the longest during the rainy season. In conclusion, the effects of season on BCS may be related to characteristics of the estrous cycle and peak progesterone levels. Ultimately, these findings provide ground knowledge to assist elephant managers and owners in planning breeding activities using seasonal effects and BCS measurements in tropical climates.

Multifaceted Interplay among Social Dominance, Body Condition, Appetitive and Consummatory Sexual Behaviors, and Semen Quality in Dorper Rams during Out-Of-Season and Transition Periods

Dorper rams (n = 24) were evaluated during the sexual resting season to determine their social rank (SR), either high (HSR) or low (LSR), under intensive management conditions in northern Mexico (25° N). Aggressive behaviors were quantified during male-to-male interactions, and appetitive and consummatory sexual behaviors during male-to-female interactions. Morphometric, live weight (LW), and body condition score (BCS) were recorded. During the early reproductive season, male-to-female behaviors were newly itemized simultaneously by seminal quality and quantity sampling. Finally, the dependent variables of the hemogram components were also quantified. Neither LW (61.25 ± 2.4 kg) nor morphometric variables differed between SR groups. However, BCS (2.25 vs. 2.66 u), sexual behaviors (i.e., approaches: 59.6 vs. 21.73 n, mating with ejaculation: 77.7 vs. 42.86 %, latency to ejaculation: 16.6 vs. 143.07 s), ejaculate volume (0.57 vs. 0.23 mL), and hemogram components favored the HSR rams (p < 0.05). Moreover, in their first male-to-female interaction, >50% of the LSR rams failed to display any sexual activity. HSR rams displayed a greater number of threatening behaviors, managing to displace LSR rams when exposed to estrus ewes during the male sexual resting season; more sexual behaviors; and an increased seminal volume in a non-live weight-dependent fashion.

Determining the factors affecting the gestational length in sheep

This research aimed to determine the effects of body weight, the body condition score (BCS), body measurements, birth type (single offspring or twin birth), birth weight and sex on the gestational length in sheep (n=111). Karayaka sheep raised on a private farm were used in the study. Progeny yield characteristics in sheep were also determined (n=139). Estrus was monitored daily using teaser rams from August to September 2016. According to our findings, the pregnancy rate, infertility rate, fecundity, and twin and single birth rates were 93.52 %, 6.48 %, 93.52 %, 14.62 % and 85.38 % respectively. The effect of age on the BCS in sheep at mating was found to be significant (P<0.05): BCS decreased as age increased. It was determined that there was a positive association between the BCS and live weight during the mating period (P<0.001). The chest circumference, front shin circumference and body length were found to be higher in sheep with a BCS ≥4.5 at mating time (P<0.01). The middle rump width was significantly affected by the BCS (P<0.001). In this study, the lowest and highest gestational lengths were found to be 148.90 and 151.41 d respectively. The gestational length in sheep was not found to be affected by age, the BCS, body measurements, sex or birth type (P>0.05); however, it was observed that the gestational lengths for male offspring and single offspring (non-multiple births) were longer. In addition, it was detected that the gestational length was different in sheep with a BCS ≥4.5. The time spent in the womb is important with respect to obtaining a healthy lamb. For profitable production, a BCS of between 2.5 and 4 is recommended in sheep. It is thought that the use of body condition scoring, which is easy information for the breeder to utilize, will have a positive effect on determining the bodily reserves of sheep and the reproductive efficiency as well as on obtaining a healthy lamb. More studies on the gestational length in sheep are required.

Supplementing Dairy Ewes Grazing Low Quality Pastures with Plant-Derived and Rumen-Protected Oils Containing Eicosapentaenoic Acid and Docosahexaenoic Acid Pellets Increases Body Condition Score and Milk, Fat, and Protein Yields

The Australian dairy sheep industry is small and mostly based on a natural grass grazing system, which can limit productivity. The current study tested different plant oil-infused and rumen protected polyunsaturated fats and their interactions with sire breeds to improve lactation traits and body condition scores (BCS) of ewes grazing low quality pastures. It was hypothesised that supplementing lactating ewe's diets with plant-derived polyunsaturated oils would improve milk production and composition without compromising BCS. Sixty ewes (n = 10/treatment) in mid-lactation, balanced by sire breed, parity, milk yield, body condition score, and liveweight, were supplemented with: (1) control: wheat-based pellets without oil inclusion; wheat-based pellets including; (2) canola oil (CO); (3) rice bran oil (RBO); (4) flaxseed oil (FSO); (5); safflower oil (SFO); and (6) rumen protected marine oil containing eicosapentaenoic acid and docosahexaenoic acid (RPO). Except for the control group, all supplementary diets included the same level of 50 mL/kg DM of oil and all diets were isocaloric and isonitrogenous. Experimental animals were grazed in the same paddock with ad libitum access to pasture, hay, and water during the 10-week study. RPO was the most effective diet that enhanced milk, fat, and protein yields by approximately 30%, 13%, and 31%, respectively (p < 0.0001). A significant increase in milk production was also observed with CO, RBO, and SFO treatments (p < 0.0001). Breed significantly influenced animal performance with higher milk yields recorded for crossbred Awassi × East Friesian (AW × EF) (578 g/day) vs. purebred Awassi (452 g/day) (p < 0.0001). This study provides empirical evidence for the use of rumen-protected and plant-derived oil-infused pellets as supplements under low quality pasture grazing conditions to improve the production performance of purebred Awassi and crossbred AW × EF ewes.

Effect of extender type and cold storage of fresh semen on reproductive indices of Karakul ewe following fixed time artificial insemination

Semen quantity and quality are affected by transportation and frequent semen collection in ram when they are transported from nucleus flock to target farms for in situ artificial insemination (AI) of ewes with fresh semen. The current study was designed to introduce the best method of fresh semen preservation for fixed time AI in Karakul sheep. The adult Karakul ewes were allocated to 6 groups (30 ewes in each group) during the breeding season and each group was inseminated with one of the following treatments, viz. fresh semen without extender, fresh semen diluted with Tris-egg yolk or milk, cooled semen (stored at 10°C for 8 h) without extender, and cooled semen diluted with Tris-egg yolk or milk. Lambing and fecundity rates were the highest when ewe was inseminated with undiluted fresh semen (71.42 and 85.71%, respectively). These reproductive indices in ewes, which were inseminated with diluted fresh semen or undiluted cooled semen were significantly lower than those recorded in inseminated ewes with undiluted fresh semen. The type of extender and storage of diluted semen at 10°C for 8 h did not significantly affect lambing rate of Karakul ewe. Results suggested that use of undiluted fresh semen and diluted fresh semen in milk or Tris-egg yolk extenders are preferable for fixed time AI in ewes of genetic improvement center and Karakul sheep flocks located near to this center, respectively.

Body condition status at mating affects gestation length, offspring yield and return rate in ewes

Abstract. The present study was planned to determine the effect of ewe body condition score (BCS) and parities on fertility, return rate, gestation length, fecundity, litter size and lamb birth weight. Data were collected from 284 heads of ewes with first to fifth parity and raised at a state farm for three consecutive (2002–2004) years. Teaser rams were used to monitor estrus twice daily in the morning and in the evening from September to October. BCSs and body weights (BWs) were recorded at mating and postpartum. The ewes, at mating time in breeding season and within first 6 h after the expulsion of fetal membranes, were divided into four groups on the basis of their BCS: thin (BCS = ≤ 2.0; n=70; 38), medium (BCS = 2.5–3.0; n=122; 142), fat (BCS = 3.5–4.0; n=72; 59) and very fat (BCS = ≥ 4.5; n= 20;17). BCSs and BWs of ewes at postpartum were highly correlated with lamb birth weight (R=0.486, P < 0.01, and R=0.130, P < 0.05, respectively). BCSs and BWs of ewes at postpartum had positive effects on lamb birth weight (Y=3.43 ± 0.10 + 0.130 + 0.047 ewe body condition score (EBCS), P < 0.01; Y= 2.92 ± 0.42 + 0.018 ± 0.009 ewe body weight (EBW), P < 0.05 kg of lamb birth weight per BCS and kilogram of ewe live weight, respectively). The fertility rate, litter size and fecundity were higher in the medium and fat groups than thin and very fat groups (χ2= 10.607, P < 0.01). The BW and BCS at postpartum affected gestation length positively (P < 0.05). Return rate or number of coitus for conception were higher (P < 0.05) in thin and very fat groups than medium and fat groups. The data revealed that the ewes with medium and fat body condition (BCS = 2.5–4.0) scores were profitable.

The effect of ewe body condition at lambing on growth of lambs and colostral specific gravity

Abstract. This study was carried out on 60 Norduz ewes to determine the effect of ewe body condition at lambing on growth of lambs and colostral specific gravity. Body condition score (BCS), ranging from 2.5 to 3.5, had no effect on lamb live weight at birth, 30, 60, 90 and 120 days of age (P  >  0.05). The average colostral specific gravity determined as 1.049 was not affected by body condition of ewes. A moderate positive correlation (r  =  0.436) was observed between condition score and live weight of ewes (P  <  0.001). The results of this study suggest that BCS is not a reliable estimator of live weight for Norduz ewes.