Influence of sexually inactive bucks subjected to long photoperiod or testosterone on the induction of estrus in anovulatory goats

The objective of this study was to evaluate the efficacy of treating sexually inactive bucks with artificial long photoperiod or testosterone on the induction of estrus in anovulatory grazing goats. A total of 91 multiparous mixed-breed anestrous goats were randomly assigned to one of three treatment groups: (1) joining with bucks subjected to 2.5 month of artificial long days (16 h of light/day; n = 31), (2) joining with testosterone-treated bucks (n = 30), and (3) joining with untreated bucks (control; n = 30). There were no differences between the light-treated (100%) and testosterone-treated (93%) bucks in their ability to induce estrus in anovulatory does. On the other hand, none of the goats in contact with control bucks exhibited estrus. The interval from start of mating to estrus was shorter in goats with the light-treated bucks (37.9 ± 4.8 h) compared with does in contact with testosterone-treated bucks (58.3 ± 8.7 h). The overall pregnancy rate in goats joined with light-treated, testosterone-treated and control bucks was 84%, 77% and 0%, respectively, with no difference (P > 0.05) between the first two groups. Anogenital sniffing, approaches, mounting attempts, and mounts were highest (P < 0.01) in light-treated bucks and lowest in control bucks. It was concluded that testosterone-treated bucks and long-day-treated bucks were equally effective in synchronizing estrus in anovulatory goats and resulted in similar levels of fertility. Given that light-treated bucks are unviable in communal production systems of goats raised by resource-poor farmers, the sexual arousal of bucks with testosterone is a practical and reliable method to induce ovulation in anovulatory goats in pastoral goat systems in hot environments.     

Effects of concentrate supplementation on carcass and meat quality attributes of feedlot finished Small East African goats

Effects of concentrate supplementation on carcass and meat quality of feedlot finished Small East African (SEA) goats were assessed using 23 animals (14.5 months old and 20.1 kg body weight). Goats were subjected to four levels of concentrate supplementation: ad libitum concentrate allowance (T100), 66% of ad libitum concentrate allowance (T66), 33% of ad libitum allowance (T33) and no concentrate (T0). All goats were slaughtered after 90 days of experimental period. The ad libitum concentrate intake attained by the goats was about 370 g DM/d. All concentrate-supplemented goats had similar (P > 0.05) total dry matter intake. T100 goats had 31 g and 14 g higher (P < 0.05) daily body weight gain than T33 and T66 goats, respectively. T100 and T66 goats were comparable in final live weight and empty body weight but both were heavier (P < 0.05) than that of T33 and T0 goats. Hot and cold carcass weights for both T100 and T66 goats were 3 kg heavier (P < 0.05) than that of T0 goats. Concentrate-supplemented goats had similar (P > 0.05) EUROP scores for carcass fatness. T100 and T66 goats had 6.5 and 3 units higher (P < 0.05) scores for conformation than T0 and T33 goats, respectively. Dressing percentage increased with levels of concentrate supplementation in a curvilinear fashion, with highest values in T66 goats. At 6 h post-mortem, muscle pH for concentrate-supplemented animals was significantly lower compared with T0 goats. Carcass fat content was 9% higher (P < 0.05) in concentrate-supplemented goats than in their contemporaries. No differences in cooking loss or shear force were observed among treatments, while these variables were affected by the type of muscle. It is concluded that feedlot finishing of SEA had limited effects on meat quality. Finishing SEA goats at 66% of their ad libitum concentrate intake, however, significantly improved weight gains and carcass fatness. Cost–benefit analyses are recommended before embarking on a large scale feedlot finishing of SEA goats.     

Consequences of variation in weaning-to-estrus interval on reproductive performance of swine females

Frequency distribution of females according to weaning-to-estrus interval (WEI) was evaluated in a database containing 15,600 breeding records of one Brazilian farm. The consequences of WEI duration on the reproductive performance was evaluated, emphasising on the effect of very short WEI (0 to 2 days). Only females with WEI up to 21 days, lactation length of 13 to 26 days and parity 1 to 8 were included in the analyses. The average WEI was 4.8 days and the percentage of females showing estrus within 2 days after weaning was 6.1%. In both primiparous (PO 1) and multiparous females (PO > 1) those with WEI of 3–5 days showed the lowest return to estrus rate. The highest RER and the lowest FR were observed when estrus occurred on the day after weaning, for primiparous sows, and on the day of weaning, for multiparous sows. In both parity classes, WEI of 0–2, 6–8, 9–12 and 13–18 days resulted in FR lower (P < 0.05) than those observed for WEI of 3–5 days. In PO 1 females, the lowest subsequent litter size (SLS) was observed in those with WEI of 6–8 and 9–12 days (P < 0.05). In PO > 1 females SLS increased significantly from WEI 0–2 to WEI 3–5 days, it decreased in females with WEI of 6–8 days and increased again in females with WEI of 9 to 21 days. A negative effect of WEI on reproductive performance is clear in females with very short WEI (0–2 days) and in those with WEI of 6–12 days.     

Effect of body condition score of does and use of bucks subjected to added artificial light on estrus response of Alpine goats

The effects of body condition score of does and exposure to sexually active bucks after exposure to long-day artificial photoperiod were examined in mature anovulatory French Alpine goat in Northern Mexico. In June, goats in good (2.3 ± 0.2, scale 1 to 4; n = 10) or poor (1.6 ± 0.3; n = 10) body condition were exposed during 15 day to sexually active bucks, which had been exposed to long photoperiod (16:8-h light–dark cycle, starting in December). A third group of goats in good body condition was exposed to bucks kept under the natural photoperiod of this region (26° N). All goats in good body condition exposed to bucks treated with prolonged photoperiod exhibited estrus behavior, whereas only 50% of the does in poor body condition showed estrous behavior during the 15-day buck exposure. None of the does in good body condition showed estrus when exposed to bucks under natural photoperiod. These results revealed that a good body condition is required for maximum estrus response in anestrous Alpine goats and that exposure of bucks to long photoperiod in winter is essential for an adequate stimulus to reestablish estrus cycles in anovulatory Alpine does in Northern Mexico.     

Effects of concentrate levels on fattening performance, carcass and meat quality attributes of Small East African × Norwegian crossbred goats fed low quality grass hay

To assess the effects of finishing Small East African × Norwegian crossbred goats with concentrate diets on the fattening performance, carcass and meat quality, 32 castrated crossbred goats (9.5 months old, 17.1 kg BWT) were equally allocated into four levels of concentrate supplementation. The concentrate levels were: Zero access to concentrate (T0), 33% access to ad libitum concentrate allowance (T33), 66% access to ad libitum concentrate allowance (T66) and 100% access to ad libitum concentrate allowance (T100). Each animal had access to ad libitum grass hay. Ad libitum concentrate intake for the goats was 663 g/d, which supported ME intake of 8.7 MJ/head/d. The attained maximum daily gain was 96 g/d. T100 and T66 goats were comparable in slaughter weight but the former had 2 kg heavier (P < 0.05) carcasses than the latter. T100 and T66 goats were similar in carcass fatness scores, though both were fattier (P < 0.05) than other diet groups. Dressing percentage (DP) was expressed in three different ways. In all but commercial DP, T100 were comparable to T66 goats, but all were higher than the other diet groups. For T0 goats, pH-values remained above 6 even after 24 h post-mortem. Cooking losses increased (P < 0.05) with increasing levels of concentrate supplementation. Moreover, among the muscles assessed, M. rectus abdominis had the least cooking loss. Warner–Bratzler shear force values of cooked muscles were highest (P < 0.05) in M. gluteobiceps, followed by M. vastus lateralis, while M. psoas major and longismus dorsi aged for 6 days had the least values. Finishing Small East African × Norwegian crossbred goats at 66% access to their ad libitum concentrate intake gives optimum carcass and meat quality, and that any increase above this level seems not to improve meat production.     

Supplementation of cottonseed meal on feed intake, digestibility, live weight and carcass parameters of Sidama goats

The experiment was conducted at Dilla Agricultural Technical Vocational Education and Training (ATVET) College in Ethiopia using twenty-four yearling intact male Sidama goats with a mean body weight (BW) of 16.8 ± 1.14 kg (mean ± SD). The objective of the experiment was to examine the effect of different levels of cottonseed meal (CSM) supplementation on the feed intake, digestibility, BW gain, and carcass parameters of Sidama goats. The experiment consisted of 90 days of feeding trial and 10 days of digestibility trial followed by evaluation of carcass parameters at the end of the experiment. The treatments included ad libitum feeding of hay (T1, control) and daily supplementation of CSM at 200 g (T2), 300 g (T3) and 400 g (T4) per head on dry matter (DM) basis. The experimental design was a completely randomized block design. The experimental goats were blocked on initial BW and six goats were randomly assigned to each treatment. Hay DM, crude protein (CP) and neutral detergent fiber (NDF) intake were higher (P < 0.001) in the non-supplemented than in the supplemented goats, however, the contrary was true for total CP intake. Total DM intake was higher (P < 0.001) for goats supplemented with the high level of CSM than those on the control treatment. Among CSM supplemented goats, the intake of CSM DM, CP, NDF (P < 0.001) and total CP (P < 0.01) were higher in the order of T4 > T3 > T2. The high level of supplementation with CSM resulted in better (P < 0.05) apparent digestibility coefficient (DC) of DM and organic matter (OM) compared to the non-supplemented goats. The apparent DC of CP was higher (P < 0.01) for supplemented than non-supplemented goats. The non-supplemented goats had lower daily BW gain, empty BW, dressing percentage on slaughter weight base, rib-eye muscle area (P < 0.01), BW change (P < 0.001), final BW (P < 0.05) and higher feed conversion ratio (P < 0.01) than the supplemented ones. The medium level of supplementation resulted in higher daily BW gain (P < 0.01), BW change (P < 0.001), final BW (P < 0.05) and lower feed conversion ratio (P < 0.01) than the lower level of supplementation, but with no differences (P > 0.05) in these parameters with the high level of supplementation. Therefore, it is concluded that supplementation of CSM at 300 g DM per head per day resulted in better animal performance parameters in Sidama goats.     

Effects of cow parity on voluntary hay intake and performance responses to early weaning of beef calves

The objective of this study was to investigate the effect of early calf weaning from both primiparous and multiparous beef cows on hay intake and measures of performance. Over two consecutive years, 96 Brahman × British cows (48 cows/year) and their calves were stratified by parity and calving date and randomly assigned to one of two weaning treatments (n = 24 cows/weaning treatment; 12 primiparous and 12 multiparous). Weaning treatments consisted of normal-weaned (calf remaining with cow throughout the study) or early weaned (calves removed from cow at 86 ± 5 days of age). An estrus synchronization and fixed-timed artificial insemination protocol (CO-Synch + CIDR) was applied to all cows at 21 days after early weaning. Following fixed-timed artificial insemination, cows were put onto bahiagrass (Paspalum notatum) pastures (3 pastures/treatment; 4 cows/pasture) for a 60-day period to evaluate voluntary hay intake. During this time, cows were provided free-choice access to grass hay (‘Florona’ stargrass; Cynodon nlemfuensis) and 2.3 kg per head daily of a urea-fortified molasses supplement. Hay intake was determined by subtracting the dried weight of residual hay from the amount offered over the 60-day evaluation period. Cow body weight and body condition score were measured on day 0 and 60. Immediately following the hay intake determination period, all cows were grouped by weaning treatment and exposed to mature Angus bulls for 21 days. Pregnancy determination to artificial insemination and natural service was determined by transrectal utrasonography on two occasions conducted 60 days after artificial insemination and again 40 days after bull removal. Multiparous cows had greater hay dry matter intake (P < 0.001), body weight (P < 0.001), and body condition score (P < 0.001) than primiparous cows throughout the study. Overall, early weaning resulted in greater than a 16% decrease (P < 0.01) in hay dry matter intake, irrespective of parity. Early-weaned cows had greater (P < 0.01) body weight and body condition score than normal-weaned cows on day 60, but not day 0. Pregnancy rate to artificial insemination was greater (P < 0.01) for multiparous compared to primiparous cows. There was a weaning treatment × parity interaction for overall pregnancy rate, whereas early-weaned primiparous, but not multiparous, cows had a greater (P < 0.05) overall pregnancy rate compared to their normal-weaned contemporaries. These data imply that early calf weaning (90 days of age) will increase body weight and body condition in both multiparous and primiparous cows; however, early-weaning provides a greater advantage to overall pregnancy rate when applied to primiparous versus multiparous cows.     

The effect of estrus synchronization treatment on somatic cell count of transitional-anestrus local-Damascus cross breed goats’ milk

An experiment was conducted to examine the effect of estrus synchronization protocols and steroid hormones concentrations on somatic cell count (SCC) of transitional-anestrus local-Damascus cross goats’ milk. Fifty-six goats (2–4-year old) were randomly assigned to three groups: fluorogestone acetate (FGA, n = 19), FGA-Prostaglandin (FGA-PGF, n = 19) and control (n = 18) groups. Intravaginal sponge containing 40 mg FGA was inserted for 13 days and an injection of 600 IU equine chorionic gonadotropin (eCG) was administered for goats of FGA and FGA-PGF groups at the time of sponge removal (day 0). In addition, goats of FGA-PGF group were injected with 10 mg dinoprost tromethamine () on day 0. Five fertile local-Damascus cross bucks were turned-in with all goats on day 0. Blood and milk samples were collected from all goats on days -13 (beginning of experiment), -6, 0, 1, 2, 7, 13 and 20 (end of the experiment). Four-year old and second-parity goats had significantly higher (p < 0.05) SCC of both udder halves than 2- and 3-year old and first-parity goats, respectively. There was a significant effect (p < 0.05) for treatment and number of kids born in the last kidding season on SCC of both udder halves. Neither estradiol nor progesterone concentrations were correlated with SCC in goats in this experiment. The SCC of both udder halves and left udder halves in goats of the control and FGA groups, respectively, increased significantly (p < 0.05) after sponge removal and buck introduction when compared with day 0, with no differences in the FGA-PGF group. This increase in SCC of the control and FGA groups coincided with peak estrus behavior. However, SCC was far below the upper limit of the current standard for normal milk. In conclusion, induction of estrus with progestagen based programs and buck introduction may cause temporary significant increase in SCC. However, the SCC values during this period of temporary increase were still in the range of acceptable values for normal milk. With the current standards for SCC of 1,000,000/ml as legal limit for abnormal milk control programs in goats, estrus synchronization programs and the estrus status should not be considered when bulk-tank milk SCC is being investigated.     

Luteal lifespan and fertility after estrus synchronization in goats

The present experiment aims to examine the efficiency of estrus synchronization using progesterone and equine chorionic gonadotrophin (eCG) and to look at luteal function. During the non-breeding and breeding season, 5 adult female Korean native goats were injected intramuscularly with 2.5 ml of physiological saline as the control. A progesterone impregnated intravaginal sponge was then kept in the same goats for 10 days followed, after a week, by an intramuscular injection of 500 IU eCG. Five adult female Nubian goats were mated with a fertile buck during the non-breeding season. During the non-breeding season 2 of the 5 goats showed a normal estrous cycle (ranging from 18 to 21 days) and 3 a short estrous cycle (ranging from 3 to 6 days). During the breeding season the equivalent figures were 1 and 2. The major axes of the corpus luteum (CL) were measured by means of calipers built into the ultrasonography system, and the concentrations of plasma progesterone (P₄) were determined by double antibody radioimmunoassay. The mean major axes of the CL in goats showing the short cycle (6.1 ± 0.5 mm) was significantly smaller than in those showing the normal cycle (8.9 ± 0.5 mm; p < 0.01) and also the value of P₄ in goats showing the short cycle (4.2 ± 2.1 ng/ml) was significantly lower than for those showing the normal cycle (10.3 ± 4.3 ng/ml; p < 0.05) at day 3 following ovulation. Three out of 5 Nubian goats became pregnant but only one goat carried to full term. The present experiment indicated that a combination of progesterone and eCG was effective in inducing estrus, although it resulted in a high incidence of short luteal lifespan. The low kidding rate and high incidence of embryonic loss may be due to the instability of the luteal lifespan.     

Use of two cloprostenol administrations 11.5 days apart efficiently synchronizes oestrus in photostimulated multiparous dairy goats in the non-breeding season

This study assessed the efficiency of synchronous oestrous induction by light programme followed by two doses of cloprostenol in acyclic Saanen goats of different parity orders. Primiparous (n = 22) and multiparous (n = 33) goats were subjected to 16 hr of light and 8 hr of darkness for 60 days (D0-D60), starting 10 days after the winter solstice. All goats received 120 µg cloprostenol doses on D130 (morning) and D141.5 (afternoon) (11.5 days apart). Oestrus behaviour, ovarian follicular dynamics and serum progesterone (P4) analyses were recorded from D0 to D174 at different intervals. Animals in oestrus after D141.5 were randomly assigned into two groups: assisted natural mating (NM) or artificial insemination (AI; 10–24 hr after oestrus onset with frozen-thawed semen). From D57 to D120, 89.0% of goats presented large follicles (5–8 mm) and P4 concentrations were subluteal from D0 to D120. More multiparous compared to primiparous goats (54.5%, 18/33 vs. 18.2%, 4/22) exhibited oestrus after both injections. More primiparous compared to multiparous goats (54.5%, 12/22 vs. 12.1%, 4/33) did not exhibit oestrus after any injection. A total of 35 goats (64%) were in oestrus after the second prostaglandin injection and were subjected to NM or AI. The conception rate was similar among primiparous (70.0%, 7/10) and multiparous (68.0%, 17/25) goats but the pregnancy rate differed, being 31.8% (7/22) and 51.5% (17/33), respectively. No interaction was found between parity order and P4 concentrations in does that became pregnant or not. Thus, the association between light programme (60 days, starting at the beginning of winter) and two cloprostenol administrations 11.5 days apart (starting 70 days after the end of the light treatment) resulted in sufficient synchronous oestrous response in multiparous acyclic Saanen goats to reach satisfactory fertility levels after both NM and AI.     

Growth and distribution of non-carcass components of Small East African and F1 Norwegian crossbred goats under concentrate diets

To assess the effects of levels of concentrate diet on growth and distribution of non-carcass components of feedlot-finished goats, 23 castrated Small East African-SEA (14.5 ± 0.5 month old and 20.1 ± 1.2 kg BWT) and 32 castrated F1 Norwegian crossbred (9.5 ± 0.5 month old, 17.1 ±1.2 kg BWT) goats were allotted to four levels of concentrate supplementation. The concentrate levels were: Zero access to concentrate (T0), 33% access to ad libitum concentrate allowance (T33), 66% access to ad libitum allowance (T66) and 100% access to ad libitum allowance (T100). Each animal had access to ad libitum grass hay. The weight of head, hocks and empty gastro intestinal tract as percentage of empty body weight (EBW) decreased (P < 0.05) with increasing levels of concentrate supplementation. The weight of liver as percentage of EBW increased (P < 0.05) with increasing levels of supplementation. Similarly, percentage of total non-carcass fat in both total body fat (TBF) and EBW increased (P < 0.05) with increasing levels of supplementation, mainly due to omental fat. Seemingly, percentages of total non-carcass fat in TBF for crossbred goats were numerically greater than that of SEA goats. Relative to EBW, liver had allometric growth coefficient greater than one, for both genotypes. Relative to both EBW and TBF, growth rate of omental fat was the fastest followed by kidney, mesenteric and pelvic fats. It is concluded that liver mass is responsive to dietary nutrient density and goats preferentially deposit fat internally as omental fat. Moreover, crossbred goats have higher proportion of non-carcass fat than SEA goats.     

Estrus induction in anestrous mixed-breed goats using the “female-to-female effect”

A trial was conducted during the anestrous period in female goats to determine: (a) whether estrus can be induced in anestrous goats by administration of equine chorionic gonadotropic hormone (eCG) and PGF_2α under pen conditions and (b) whether these sexually active female goats can elicit sexual arousal in sexually inactive bucks. One hundred and fifteen pluriparous, nonlactating mixed-breed female goats were randomly assigned to one of four treatment groups: (1) administration of a single dose of 240 IU of eCG, 50 μg PGF_2α i.m., and 25 mg progesterone (P₄) (eCG; n?=?30); (2) administration of P₄ and exposure to female goats treated with eCG–PGF_2α (P₄; n?=?39); (3) administration of 0.5 ml saline and P₄ (Sal; n?=?23); and (4) P₄ plus exposure to female goats treated with saline (Con; n?=?23). After hormone administration, all goats were put together with adult sexually inactive bucks for 15 days. The percentage of goats in estrus during these 15 days was similar in eCG-treated animals and untreated animals exposed to the eCG animals (97 and 95 %). Pregnancy rate was also similar (63 vs. 64 %) between these two groups. eCG-treated goats exhibited estrus earlier (P?<?0.05) than the treated goats in contact with the eCG goats. Furthermore, eCG-treated goats had larger litters (1.9?±?0.2 vs. 1.6?±?0.1, P?<?0.05) than the untreated goats in contact with the eCG goats. These results show that fertile estrus can be induced in anestrous female goats by exposing them to female goats induced to estrus with eCG. This female–female interaction triggers the stimulation cycle leading to the sexual arousal of bucks.     

Polyethylene glycol influences feeding behaviour of dairy goats browsing on bushland with different herbage cover

The effects of supplemental polyethylene glycol (PEG) on feeding behaviour, diet composition, intake and milk production were studied in late lactating Sarda goats browsing on a lentisk-based bushland with different herbage cover. The goats were allotted to two groups that browsed 7 h daily on 2 plots characterised by different cover proportions of woody and herbaceous species. These proportions were 90% woody vs. 10% herbaceous species in one plot (W — woody, close bushland with low herbage cover) and 70% woody vs. 30% herbaceous species in the other plot (H — herbaceous, open bushland with high herbage cover). Each group was divided into two sub-groups: one fed with 50 g day^− 1 of PEG 4000 MW (PEG⁺) and the other receiving no PEG supplementation (PEG⁻). The feeding behaviour was different between groups; goats in herbaceous plot (H-goats), had a longer grazing time, expressed as percentage of total observation time than the counterparts (64% vs. 58%, P < 0.05). The intake was not affected by the treatments. The percentage of the species eaten by the goats was different in the two groups: H-goats ate more herbaceous and less woody species than goats in woody plot (W-goats). In each group the PEG tended to affect the botanical composition of the diet. PEG dosed goats ate more tanniferous species than control counterparts (P = 0.12). The average daily milk production was 473, 591, 541 and 589 ml, respectively in W-PEG^−, W-PEG⁺, H-PEG⁻ and H-PEG⁺ sub-groups with significant effect of herbage cover × PEG dose interaction (P < 0.05). The milk urea was affected by herbage cover (P < 0.001) and PEG supplementation (P < 0.001). In conclusion, the effect of PEG is strictly dependent on pasture composition. In open bushland, featured by moderate woody cover, the effect of PEG is more intense on diet selection, due to its marked post-ingestive effects. In close bushland, characterised by high proportion of tanniferous species prevails the efficacy of PEG as a performance booster.     

Influences of dietary regimens on microbial content in gastrointestinal tracts of meat goats

This experiment was conducted to evaluate the effects of dietary treatments on microbial loads and pH of gastrointestinal tract contents in meat goats, as well as the concentration of volatile fatty acid (VFA) in the rumen. Crossbred (Boer x Spanish) goats (n = 36; BW = 17.7 kg) were assigned randomly to one of three experimental diets (n = 12/diet or 3 pens/treatment) for 90 days:alfalfa (Medicago sativa) hay alone (AH-diet); 18% CP concentrate alone (C-diet); or, a combined diet (AHC-diet), consisting of the AH-diet for the first 45 days, followed by 45 days of the C-diet. After evisceration, pH values of rumen liquor and colon digesta were immediately measured from each animal, as well as aseptically collected rumen liquor and rectal samples to determine the microbial loads. Collected rumen liquor was also prepared for volatile fatty acid (VFA) contents. Feeding meat goats with alfalfa hay alone had higher (P < 0.05) rumen (7.17) and colon (7.10) pH compared with those fed either the concentrate alone or combined-diet. Although the acetate content was high in the AH-fed group (66.3 mM) compared to the AHC-diet group (34.6 mM), no significant differences were found in the total VFA contents in rumen liquor among the goats fed three different dietary regimens. Total plate counts were not significantly different among goats fed the experimental diets in the rumen or rectal samples. Escherichia coli counts in the rectal samples were lower (P < 0.05) in the AH-diet group (6.43 log₁₀ CFU/g) compared with the C-diet (8.21 log₁₀ CFU/g) or AHC-diet (8.40 log₁₀ CFU/g) groups. However, no significant differences were found in the E. coli counts of rumen samples from goats fed the experimental diets. The mean (± SEM) rumen E. coli counts were 1.38, 1.65, and 2.51 ± 0.560 log₁₀ CFU/g in the AH-, C-, and AHC-diet groups, respectively. The results indicate that feeding hay alone may decrease the fecal shedding of E. coli in meat goats with increasing the rumen and colon pH.     

Utilization of citrus pulp based diets and Enterolobium cyclocarpum (JACQ. GRISEB) foliage by West African dwarf goats

Sixteen West African dwarf goats weighing 5.0–5.6 kg were used in an experiment that lasted 112 days to investigate the utilization of citrus pulp based diets and E. cyclocarpum. A control diet which contained 88.5% dried brewers' grains (DBG) and other three experimental diets in which DBG was replaced with dried citrus pulp (DCP) at 25, 50 and 75% levels, respectively constituted the four treatments. The goats were divided into four groups of four animals each to balance for variation in live weight before they were assigned to the four different experimental diets. Significant differences (P < 0.05) were obtained in growth rate with (22.14–34.02 g/d) the highest and lowest value from 50 and 75% DCP inclusion respectively. The digestibility coefficients of DM, Ash, NFE, NDF, ADL, cellulose and hemicellulose increased with increasing levels of dried citrus pulp in the diets and were highest at 75% level of replacement. However, the CP digestibility of 83.85% was highest in the control diet and was significantly (P < 0.05) different from other diets containing citrus pulp. Nitrogen intake (g/d) decreased significantly (P < 0.05) with increasing levels of dried citrus pulp in the diets from 45.57–33.28 and was lowest in the control diet. Nitrogen balance also followed the same trend, being highest (42.07 g/d) at 25% DCP and lowest at 75% DCP. The Packed cell volume (PCV), haemoglobin concentration (Hb), red blood cells (RBC), white blood cells (WBC) and total blood protein (TBP) were significantly (P < 0.05) different across the dietary treatments at the start and end of the trial. The values for PCV, RBC, MCH, glucose and total protein decreased slightly in the control diet. Serum glutamate pyruvate transaminase (SGPT) values also increased significantly (P < 0.05) with increasing levels of dried citrus pulp in the diets at the end of the experiment and were highest (6.50 IU/L) at 75% level of citrus pulp. Therefore, the efficient utilization of citrus pulp and E. cyclocarpum by WAD goats was attained at the 50% level of inclusion in the diets.     

Effect of scrotal bifurcation on breeding soundness traits in Beetal bucks during summer season

Relationship of scrotal bifurcation or splitness with breeding soundness traits was investigated in 15 Beetal bucks (17–20 months of age and 48.72?±?1.57 kg mean BW). Breeding soundness traits of conjoined/unsplit (n?=?6) scrotal bucks was compared with split (n?=?9) scrotal bucks having lengthwise >?1 in. bifurcation. Two consecutive semen ejaculations per buck were collected at monthly interval during summer season (April to June 2018) using intact buck as teaser and sexual behavior was simultaneously recorded. Scrotal morphometry parameters, i.e., scrotal circumference, scrotal volume, scrotal skin thickness, testis length, width, and thickness were also recorded. Bucks with split scrotum had relatively more scrotal dimensions (scrotal circumference (P?<?0.01), scrotal volume (P?<?0.01), testis length (P?<?0.01)) than conjoined scrotal bucks. Among various semen attributes, semen volume of first ejaculate (P?<?0.01), second ejaculate (P?<?0.05), mean semen volume (P?<?0.01), total sperm count of first ejaculate, and mean sperm count of both ejaculates were more (P?<?0.01) in split scrotal bucks. However, scrotal bifurcation had no influence on sexual behavior of bucks. It is concluded that Beetal bucks with split scrotum had relatively better breeding efficiency traits than conjoined scrotal bucks.

     

Effect of milking frequency in early lactation on energy metabolism, milk production and reproductive performance of dairy cows

The objective of this study was to evaluate the effect of imposing different milking frequencies for the first 4 weeks of lactation on energy balance, blood metabolic profiles and reproductive performance. The milking frequencies imposed were once daily for the first 4 weeks of lactation and twice daily subsequently (X1), twice daily for the entire lactation (X2) and three times daily for the first 4 weeks of lactation and twice daily subsequently (X3). Two weeks prior to the first expected calving date, sixty-three multiparous, Holstein-Friesian cows, were allocated to treatments based on expected calving date, parity (lactation number = 2 and lactation number > 2), BCS and BW. Mean DMI was lower (P < 0.05) on X1 than X2 (15.7 and 17.1 kg/day) over the first 4 weeks of lactation, but DMI on X3 was not different to either. Milk yield was lower (P < 0.05) on X1 than on X2 and X3 (24.1, 31.9 and 31.4 kg/day) from weeks 1 to 4 and at week 10 of lactation (30.9, 33.9 and 33.7 kg/day) but was not different at week 20. Yield of milk constituents followed the same pattern as milk yield. Milking frequency had no significant effect on milk fat or protein concentration but milk lactose concentration was higher (P < 0.05) on X1 than on X2. Cows on X1 experienced less (P < 0.05) negative energy balance than those on X2 and X3 from weeks 1 to 4, with no difference between X2 and X3. Cows on X1 lost less BW (P < 0.05) from weeks 1 to 4 and lost less BCS up to day 73 of lactation than cows on X2 and X3. Plasma NEFA and BHB concentrations tended to be lower and plasma glucose tended to be higher on X1 than on X2 and X3 from weeks 1 to 4, while plasma insulin was higher on X1 than on X2 and X3 for the first 2 weeks of lactation. There was no difference between treatments in any reproductive performance variable measured. These results indicate that reduced milking frequency decreases milk yield and improves energy balance and metabolic status in early lactation.     

Effects of treating rice straw with urea or urea and calcium hydroxide upon intake, digestibility, rumen fermentation and milk yield of dairy cows

Three, multiparous Holstein crossbred dairy cows with initial body weight of 385 ± 19 kg were randomly allocated to 3 treatments of rice straw (T1 = untreated rice straw; T2 = 5.5% urea-treated rice straw (5 g urea in 100 ml water to 100 g air-dry (91% DM) straw); T3 = 2.2% urea + 2.2% calcium hydroxide treated rice straw (2.0 g urea and 2.0 g Ca(OH)₂ in 100 ml to 100 g air-dry (91% DM) straw) according to a 3 × 3 Latin square design. Each period lasted for 21 days in which feed, feces and rumen fluid were collected during the last 7 days for chemical analyses. The findings revealed significant improvements in dry matter intake and digestibility by using 5.5% urea-treated rice straw and 2.2% urea + 2.2% calcium hydroxide treated rice straw. Ruminal pH and NH₃-N were found higher (P < 0.05) as compared with urea-treated rice straw fed group, while blood urea nitrogen and milk urea nitrogen were in normal ranges. Volatile fatty acid concentrations especially those of acetic acid were decreased (P < 0.05) and those of propionic acid were increased (P < 0.05), thus acetic acid:propionic acid was subsequently lowered (P < 0.05) in cows fed with 5.5% urea-treated rice straw and 2.2% urea + 2.2% calcium hydroxide treated rice straw, respectively. Moreover, ruminal viable and cellulolytic bacterial counts were enhanced by urea and calcium hydroxide treatments. Milk protein and fat concentrations were additionally increased by respective treatments while 3.5% fat-corrected milk was highest; ranking from 2.2% urea + 2.2% calcium hydroxide treated rice straw, 5.5% urea-treated rice straw and urea-treated rice straw fed groups. Based on this study, implications could be made that using 2.2% urea + 2.2% calcium hydroxide treated rice straw for straw treatment could be an alternative treatment to 5.5% urea treatment with regards to its effectiveness and treatment cost for lactating dairy cows.     

The effect of high calcium intake by pregnant Awassi ewes at late gestation on minerals status and performance of ewes and newborn lambs

Calcium (Ca) requirement increase rapidly by pregnant ewes at late gestation as a result of high fetal growth. Furthermore, Ca deficiency results in poor growth and bone development in growing newborn lambs. The aim of this study was to evaluate the effect of calcium supplementation (Calcium carbonate–CC) and vitamin AD₃E injection (75,000 IU/shot) to pregnant Awassi ewes at late gestation (− 45 days prepartum) on their mineral levels and performance of their newborn lambs. Forty pregnant Awassi ewes at late gestation (65 ± 6.1 kg) were selected before parturition (− 45 days; using hormonal sponges for estrus synchronization) and randomly divided to 4 dietary treatments. The treatments were: group 1 Control (1.4% CC); group 2 (2.4% CC); group 3 (1.4% CC + 2 shots vitamin AD3E at − 45 and − 21 days prepartum); group 4 (2.4% CC + 2 shots vitamin AD3E at − 45 and − 21 days prepartum). Blood samples were collected from ewes (− 45, 0 days prepartum: 30 and 60 days postpartum) and lambs (0, 30 and 60 days old). Average milk yield and samples were collected. Body weights of lambs were taken at birth, 30 and 60 days old. Blood serum and milk samples were prepared and analyzed by AAS for Ca, Mg, Co, Mn and Cu concentrations.Calcium concentrations in bloods serum of ewes, 0 and 60 days postpartum, and lambs at weaning (60 days old) from group 4 were significantly (P < 0.05) higher compared to other groups. No significant effect (P > 0.05) of treatment on Co, Mg and Cu in blood serum of ewes and lambs except for Cu concentration in ewes. Moreover, a significant increase (P < 0.01) in milk inorganic% (30 and 60 days samples) in ewes from group 2 when compared with other groups. The average milk yield (AMY) of ewes from group 2 and 4 at late stage of lactation (45–60 days) were significantly higher (P < 0.05) compared to groups 1 and 3. In addition, Ca% in colostrums samples from ewes in groups 2 and 4 were significantly higher (P < 0.01). The average daily gain (ADG) and total body gain for lambs up to weaning (60 days old) were significantly higher (P < 0.05) in groups 1 and 2 compared with the other groups.In conclusion, increasing level of Ca intake in feed of Awassi ewes at late gestation, with or without vitamin AD₃E injections, improve the calcium concentration in colostrums and blood serum of ewes and their lambs without negative effect in their health and performance.     

Number of services and the reservice intervals in relation to suboptimal reproductive performance in female pigs on commercial farms

This study investigated the associations of the number of services, reservice intervals (RI), parity, and weaning-to-first-mating intervals (WMI) with farrowing rate and pigs born alive (PBA) on commercial farms. The selected 117 farms included 115,442 service records and 93,867 farrowing records in 54,502 female pigs (females). A service was defined as one or more mating events within a 10-day time period of estrus. The number of services was categorized into three groups: non-return to service, first reservice, and second or later reservice. The RI was divided into 8 seven-day interval groups from 11 to 66 days and a group of 67–150 days. The effects of the number of services, RI, WMI, and parity on farrowing rate and PBA were analyzed by using the mixed-effects models. The frequency distributions of non-return to service, first reservice, and second or later reservice groups were 88.6, 9.7, and 1.7%, respectively. Farrowing rate decreased by approximately 18% with each service (P < 0.05). Reserviced females exhibited a different reproductive performance as compared to non-return to service females depending on parity and WMI. In the non-return to service group, sows with WMI 7–12 days had the lowest farrowing rate (P < 0.05). Meanwhile, in the first and second or later reservice groups, no differences between the WMI groups were found in farrowing rate. At parity 1 and 2, the first reservice group had the most PBA (P < 0.05). However, at parity 0, 3–5, and ≥ 6, no differences between the number of service groups were found in PBA. In the WMI 0–6 and 7–12 day groups, the first reservice group had the most PBA (P < 0.05). The mean of RI was 44.5 ± 0.28 days in 13,183 reservice records. RI decreased from 47.4 to 39.2 days as parity increased from 0 to ≥ 6 (P < 0.05). The frequency distributions of the RI 18–24, 39–45, and 67–150 days were 39.3, 12.4, and 18.8%, respectively. Gilts had lower proportions of the RI 18–24 days and higher proportions of RI 67–150 days than sows at parity 3–5 (P < 0.05). No differences between RI groups were found in farrowing rate and PBA. Increasing farrowing rate in non-return to service females and minimizing RI in females at low parity improved herd productivity.