Feed intake and production parameters of lactating crossbred cows fed maize-based diets of stover,silage or quality protein silage

Thirty-six Boran × Friesian dairy cows (392 ± 12 kg; mean ± SD) in early parity were used in a randomised complete block design. Cows were blocked by parity into three blocks of 12 animals and offered normal maize (NM) stover (T1), NM silage (T2) or quality protein maize (QPM) silage (T3) basal diets supplemented with a similar concentrate mix. Feed intake, body weight and condition changes and milk yield and composition were assessed. The daily intake of DM, OM, NDF and ADF for cows fed the NM stover-based diet was higher (P < 0.05) than for the cows fed the NM silage and QPM silage-based diets. However, the daily intake of DOM (9.3 kg) and ME (140.8 MJ) for cows on QPM silage-based diet was higher (P < 0.05) than for cows on NM stover-based diet (8.4 kg and 124.2 MJ) and NM silage-based diet (7.9 kg and 119.1 MJ). Body weight of cows was affected (P < 0.05) by the diet, but diet had no effect (P > 0.05) on body condition score, milk yield and milk composition. The digestible organic matter in the NM stover-based diet (724 g/kg DM) was lower (P < 0.05) than that in the NM (770 g/kg DM) and QPM silage-based diet (762 g/kg DM). It was concluded that the performances of the cows on the NM silage and QPM silage diets were similar and were not superior to that of the NM stover-based diet.     

Effects of different levels of dried sweet potato (<Emphasis Type="Italic">Ipomoea batatas</Emphasis>) leaves inclusion in finisher ration on feed intake,growth, and carcass yield performance of Ross broiler chicks

The effect of supplementation with increasing levels of dried leaves of sweet potato (Ipomoea batatas) on feed intake, body weight gain, and carcass yield characteristics of finisher Ross broiler chicks was studied at Haramaya University, Ethiopia. Three hundred Ross broiler chicks aging 29 days and weighing 540 ± 5.28 g (mean ± SD) were randomly distributed to 15 pens, each with 20 chicks, representing five treatment rations each with three replications. Dietary treatments consisted of inclusions of dried leaves of sweet potato at levels of 0, 50, 100, 150, and 200 g/kg DM for treatments T1, T2, T3, T4, and T5, respectively. The experiment lasted for 28 days, during which, dry matter intake (DMI), body weight gain, and feed conversion efficiency; carcass yield characteristics; and weights and lengths of different parts of gastrointestinal tract were measured. Data were subjected to statistical analysis using SAS (1998). Inclusion of dried leaves of sweet potato at the level of 200 g/kg DM resulted in lower (P < 0.01) daily DMI as compared to chicks in control diet (T1). The daily body weight gain declined (P < 0.01) when the level of dried leaves of sweet potato in the diet was 150 and 200 g/kg DM. Inclusion of dried leaves of sweet potato up to 100 g/kg DM did not affect (P > 0.05) eviscerated carcass weight, and weights of drumstick with thigh and breast meat were not affected (P > 0.05) by inclusion of dried leaves of sweet potato up to 150 g/kg DM. The results of this study revealed that inclusion of dried leaves of sweet potato up to 100 g/kg DM in the finisher ration might be considered as the optimum level of supplementation when chickens are sold on live weight basis, but if birds are sold on eviscerated carcass weight basis, inclusion up to 150 g/kg DM might be economically feasible as it produced higher carcass yield components.     

Milk yield and quality in Guernsey cows fed cottonseed cake-based diets partially substituted with baobab (<Emphasis Type="BoldItalic">Adansonia digitata</Emphasis> L.) seed cake

The objective of this study was to determine the effects of partially substituting cottonseed cake with graded levels of baobab (Adansonia digitata L.) seed cake (BSC) on milk yield and quality in Guernsey cows. Sixteen cows in mid-lactation and in their third parity were allocated to diets containing 0% (control), 5%, 10%, and 15% BSC in a completely randomized design. Each cow was given a daily feed ration of 6 kg and a basal diet of soya bean stover ad libitum. There were no differences in daily feed intake (P > 0.05), but basal intake differed among all treatment groups with cows on the control diet having the highest intake (30 ± 0.34 kg/day). Mean daily milk yield differed (P < 0.05) among all treatment groups. However, the control had higher milk yield of 12.1 ± 0.73 kg/day, and the 15% BSC had the least yield of 7.46 ± 0.73 kg/day. Cows on the control diet had higher milk butterfat content (6.12%; P < 0.05) than those on the BSC-based diets. Protein content differed (P < 0.05) across all treatment groups with cows on 15% BSC producing the highest protein content (3.43%) while the control had the least (2.6%). The concentration of milk total solids for cows fed on 15% BSC was higher (P < 0.05) than that from cows on other diets. Lactose content was not affected by the diets (P > 0.05). These results indicate that BSC can substitute soya bean cake in dairy diets, but milk production and butterfat content are compromised.     

Circadian rhythm of metabolic changes associated with summer heat stress in high-producing dairy cattle

The current study aimed to investigate the circadian rhythm of blood metabolic parameters associated with summer heat stress (HS) in dairy cows. Ten healthy lactating Holstein Friesian cows were followed during HS for three successive days at six different time points. Blood was sampled from each cow starting from 07:00 am; at 4-h intervals. Ambient air temperature and relative humidity were recorded, and temperature-humidity index (THI) was calculated as well. Respiration rate (RR) and rectal temperature (RT) were recorded for each cow at the time of blood sampling. Concentrations of glucose, non-esterified fatty acids (NEFA), total cholesterol (TC) and urea were measured in each blood sample. The THI values were >68 at all times of the day, and the highest values were recorded at 11:00 am, 03:00 pm and 07:00 pm (80.9, 83.7, and 80.8, respectively). All the cows showed a significantly higher RR and RT coinciding with higher THI values (93 ± 4 and 39.6 ± 0.1; 90.2 ± 3.4, and 40.1 ± 0.1; 87.6 ± 4.1, and 39.8 ± 0.1, respectively, P < 0.05). The concentrations of glucose were the lowest at 11:00 am and 03:00 pm (3.75 ± 0.1 and 3.44 ± 0.1 mmol/L, respectively, P < 0.05). Decreased glucose concentrations coincided with increased NEFA concentrations, (0.43 ± 0.01 and 0.56 ± 0.02 mmol/L, respectively, P < 0.05), and were highly negatively correlated (r = −0.50, P < 0.001). The highest urea and TC concentrations were registered at 11:00 am (6.11 ± 0.15 mmol/L and 109.9 ± 2.2 mg/dl, respectively) whereas the lowest urea and TC values were recorded at 03:00 am (4.97 ± 0.18 mmol/L and 99.5 ± 1.7 mg/dl, respectively, P < 0.05). The results of the present study indicate that there was a circadian variation in glucose, NEFA, urea, and TC resulting in the most unfavorable metabolic condition during the hottest moment of the day in dairy cattle. Earlier work revealed that HS-metabolic changes are reflected in the follicular fluid. The circadian changes observed in the present study associated with HS may imply that also the microenvironment of the oocyte is affected.     

Performance and carcass measurements of ewe lambs reared in a feedlot and fed wheat (<Emphasis Type="BoldItalic">Triticum durum</Emphasis> Desf.) middlings total mixed rations in the summer season

The effect of total mixed ratios containing wheat middlings (WM) as a corn grain substitute on the growth performance and carcass traits of Comisana ewe lambs was evaluated. Forty ewe lambs, with average live body weight of 13 ± 0.3 kg (mean ± SEM), were allocated randomly to two isocaloric and isonitrogenous diets for 50 days. Control diet contained 400 g/kg of dry matter (DM) of corn as the main starchy source, whereas experimental diet contained 600 g/kg DM of WM. In vivo nutrient apparent digestibility of the two diets was determined using Comisana rams (mean body weight, 65 ± 2.3 kg) and indicated significant (P < 0.05) differences for neutral detergent fibre, acid detergent fibre, cellulose and hemicellulose fractions. Results from the trial using Comisana ewe lambs showed that growth traits were unaffected by dietary treatments as well as none of the carcass measurements examined (P > 0.05). These findings indicate that WM results as a suitable feed ingredient for growing ewe lambs that can be a satisfactory substitute to conventional grain source.     

Effect of supplementing crossbred Xhosa lop-eared goat castrates with <Emphasis Type="Italic">Moringa oleifera</Emphasis> leaves on growth performance,carcass and non-carcass characteristics

The objective of the study was to determine the effect of supplementing Moringa oleifera leaves (MOL) on growth performance, carcass and non-carcass characteristics of crossbred Xhosa lop-eared goats. A total of 24 castrated goats aged 8 months, with a mean initial weight of 15.1 ± 2.3 kg, were randomly divided into three diet groups with eight goats in each. The duration of the trial was 60 days. All goats received a basal diet of grass hay (GH) ad libitum and wheat bran (200 g/day each). The MOL and sunflower cake (SC) groups were fed additional 200 g of dried M. oleifera leaves and 170 g of SC, respectively. The third group (GH) did not receive any additional ration. The crude protein of MOL (23.75%) and SC (23.27%) were higher (P < 0.05) than that of the GH diet (14.08%). The attained average daily weight gain for goats fed MOL, SC and GH were 103.3, 101.3 and 43.3 g, respectively (P < 0.05). Higher (P < 0.05) feed intakes observed were in SC (491.5 g) and MOL (490.75 g) compared with GH (404.5 g). The hot carcass weight was higher (P < 0.05) for SC (10.48 kg) and MOL (10.34 kg) than for the GH group (8.59 kg). The dressing percentage in SC (55.8%) and MOL (55.1%) were higher (P < 0.05) than that of the GH (52.9%). The growth performance and carcass characteristics of SC and MOL goats were not different. Feeding MOL or SC improved the growth performance and carcass characteristics of goats in an almost similar way, which indicates that M. oleifera could be used as an alternative protein supplement in goats.     

Effect of feeding calcium salts on performance of nursing Awassi ewes

Twenty nursing Awassi ewes (BW = 50 ± 2.35 kg, age = 4.5 ± 1.2 years) with their lambs were used to evaluate the effects of feeding calcium salts in lactation diets on performance and pre-weaning growth of their lambs. Treatments were 0% calcium salts (CON) or 5% calcium salts (FAT). At the end of the study, a digestibility experiment was performed. Milk yield was greater (P < 0.05) for ewes fed the FAT diet than the CON diet. Milk composition was similar (P > 0.05) between diets. However, milk energy value (kcal/day) tended to be greater (P = 0.07) for the FAT diet than the CON diet. Concentrations of milk C18:1c9 and C20:0 were greater (P < 0.05) in ewes fed the FAT diet than the CON diet. However, concentration of trans-10, cis-12 CLA was lower (P = 0.05) in the FAT diet than in the CON diet. No differences in feed intake and body weight change were detected between diets. Digestibility of dry matter, organic matter, crude protein, ether extract, neutral detergent fiber, and acid detergent fiber were similar (P > 0.05) for diets. For lambs, weaning weight was not affected by treatments. However, average daily gain and total gain were greater (P = 0.053) for the FAT diet than the CON diet. Results suggest that supplementing lactating ewes with calcium salts at the beginning of lactation phase improves daily milk yield of ewes and pre-weaning growth of their lambs with no major negative impact on feed intake and digestibility.     

Supplementation of cottonseed,linseed, and noug seed cakes on feed intake,digestibility, body weight,and carcass parameters of Sidama goats

A digestibility, feed intake, and carcass evaluation experiment using 20 yearling intact male Sidama goats weighing 16.4 ± 0.63 kg (mean ± SD) was conducted in Ethiopia with the objectives to determine feed intake, digestibility, body weight (BW) gain, and carcass parameters. The treatments included feeding natural pasture hay (T1, control) and supplementation with cottonseed cake (284 g—T2), linseed cake (250 g—T3), and noug seed cake (296 g—T4) on dry matter (DM) basis to supply 85 g crude protein (CP) per head per day. Randomized complete block design for feed intake and BW parameters and complete randomized design for digestibility and carcass parameters were used. Hay DM intake was higher (P < 0.01) for T1 than for the other treatments. T3 promoted higher (P < 0.01) DM (29.3 g/kg W^0.75/day) and CP (14.1 g/kg W^0.75/day) intake than T4 (8.9 g/kg W^0.75/day DM and 4.1 g/kg W^0.75/day CP). T3 showed better (P < 0.05) organic matter and CP digestibility than T2. Goats in T3 had higher nitrogen intake (P < 0.01) and retention (P < 0.05) than those in T1. Goats in T2 and T3 showed higher (P < 0.05) daily BW gain and final BW than those in T4 and T1. Goats in T2 and T3 had higher (P < 0.05) slaughter weight, empty BW, hot carcass weight, rib-eye muscle area, and dressing percentage on slaughter weight basis than those in T1. The results showed that T2 and T3 had similar effect on CP intake, daily BW gain, and carcass parameters for growing Sidama goats fed natural pasture hay.     

Effects of first postpartum progesterone rise,metabolites, milk yield,and body condition score on the subsequent ovarian activity and fertility in lactating Holstein dairy cows

Seventy multiparous healthy lactating Holstein cows (fat-corrected milk yield = 7,561.8 kg) were monitored from 14 days before to 70 days after calving. Transrectal ultrasound scanning was performed twice weekly from 7 to 65 days postpartum. Blood samples were also collected twice weekly to measure serum P₄ and biweekly to detect serum β-hydroxybutyrate (βHB) and nonesterified fatty acid (NEFA) concentrations. Body condition score (BCS) was taken biweekly after calving. Based on the serum P₄ profile of 59 cows (11 cows were excluded due to the occurrence of postpartum diseases) studied, 27 (45.8%) had normal ovarian activity, while 21 (35.6%), six (10.1%), three (5.1%), and two (3.4%) had delayed ovulation (DOV), prolonged luteal phase (PLP), short luteal phase (SLP), and cessation of ovarian activity, respectively. Cows with PLP had an earlier ovulation compared to that of cows with normal ovarian activity (23.16 ± 4.02 vs 31.9 ± 8.35 days; P < 0.05). PLP cows also had a greater mean ± standard deviation peak milk yield (44.2 ± 5.8 vs 37.2 ± 5.7 kg/day, 75 days postpartum; P < 0.05) than cows with normal postpartum ovarian activity. The PLP group also had greater milk production in the previous lactation period. Logistic regression analysis indicated that cows with P₄ concentration ≥1 ng/ml on day 24 after calving were more at risk for PLP by 1.1 for each 1 kg increase in mean peak milk yield during 75 days after calving. BCS was lower in cows with DOV compared to that of cows with normal ovarian activity at any time after calving (P < 0.05). Serum βHB concentrations in DOV cows were significantly higher than that of normal cows on day 42 after calving (0.69 ± 0.29 vs 0.54 ± 0.12 mmol/L, P < 0.05). No significant difference was found in the mean concentrations of NEFA between cows in different groups at any time after calving (P > 0.05). The concentrations of P₄ on days 28 and 31 were negatively correlated with βHB concentration on day 42 after calving in cows with normal ovarian activity (R = −0.44, P = 0.02). In conclusion, these findings suggest that early ovulation and hence early postpartum P₄ rise in addition to the high milk production could partly be responsible for the occurrence of PLP in dairy cows.     

Behaviour of crossbred does and their kids at parturition under extensive and intensive conditions

Data from 82 kiddings from mixed-breed (native x dairy goats) goats reared on rangeland (n = 47) or confinement (n = 35) were used to determine the influence of various factors on length of labour, standing of newborn kids and time to first suckling in pluriparous goats. Both groups were mated at the same time to bucks of the same genotype in February. During the kidding time in July, the goats were monitored for 24 h in order to register parturition traits and kid birth weight and body measurements. For all goats, blood samples were collected at parturition in order to establish the nutritional state of goats. Grazing goats had lower body weight and body condition score (P < 0.01) than pen-fed goats, as well as lower values for some blood metabolites indicative of low body energy reserves. For both grazing and pen-fed goats, the majority of kiddings (>93%) occurred during daylight hours. No kiddings were registered from 2300 to 0500 hours. No effects of height at withers, thoracic circumference and sex of kids at birth were found to influence length of labour. Labour was shorter (P < 0.01) for pen-fed does than grazing goats (10.6 ± 1.18 min vs. 15.4 ± 1.2 min; mean ± SD). The length of parturition was considerably longer (P < 0.05) for twin-bearing does than for single-bearing does (16.6 ± 1.76 min vs. 11.2 ± 0.81 min, respectively). The interval between parturition and standing of kids was shorter (P < 0.05) for kids from litters weighing >3.3 kg (entire litter) than kids from litters with <3.3 kg (22.7 ± 1.82 min vs. 31.1 ± 2.76 min). Time to first suckling was longer (P < 0.05) for kids delivered from pen-fed does than kids from grazing does (57.8 ± 7.57 min vs. 42.9 ± 3.05 min). These results confirm that, independently of type of production system (intensive or extensive), kiddings of does are concentrated during daylight hours. These results also indicate that conformation of kids does not alter duration of labour, and that nutritional stress of goats during gestation (extensive conditions) does not interfere with the neonate’s level of alertness and arousal.     

Effect of dietary monensin inclusion on performance,nutrient utilisation,rumen volatile fatty acid concentration and blood status of West African dwarf bucks fed with basal diets of forages

This experiment investigated the effect of dietary monensin on performance, nutrient utilisation, rumen volatile fatty acid and blood status in West African dwarf (WAD) goats fed with basal diets of forages. Four concentrate supplements were formulated to include 0 (MO), 15 (M15), 30 (M30) and 45 (M45) mg monensin/kg dry matter. Twenty-four WAD bucks (7.3 ± 1.20 kg initial body weight, aged 9–12 months) were randomly allotted to four experimental diets in a completely randomised design for 90 days, six animals per diet. Results indicated that animals fed M15, M30 and M45 diets had lower (P < 0.01) dry matter and water intake than those fed M0 diet. Crude protein and neutral detergent fibre intakes by the bucks followed similar trend. Animals on M15, M30 and M45 had better (P < 0.001) feed and protein efficiency ratio than those fed M0 diet. Rumen pH and total volatile fatty acid concentration were maintained (P > 0.05) while monensin decreased (P < 0.001) acetate/propionate ratio. Blood glucose increased (P < 0.001) from 59.1 mg/dl in animals on M0 diet to 67.8, 66.0 and 66.3 mg/dl in animals on M15, M30 and M45 diets. Overall, there were no variations among animals on M15, M30 and M45 diets. It is concluded that feeding monensin at 15 to 45 mg/kg DM of supplemental concentrate diets to West African dwarf bucks could be effective in improving feed and protein efficiency, manipulating the rumen for increased propionate production and increasing blood glucose levels.     

Environmental factors and interval from the introduction of rams to estrus in postpartum Saint Croix sheep

The objective of this study was to determine whether season and total rainfall during the breeding season, sheep parity, and/or litter size affect the interval from the introduction of rams to estrus (IRE) in hair Saint Croix sheep in northeastern Mexico. An analysis was made of 874 services performed during 9 years, introducing the rams into the sheep flock after an isolation period of 60 days during the postpartum period. Estrus was recorded twice daily during 35 days. Year and season influenced significantly on the interval between ram introduction and estrus length (P < 0.01). Winter IRE length (7.9 ± 0.1 days) was shorter than in the other three seasons (11.1 ± 0.2, 11.1 ± 0.1, and 16.2 ± 0.2 days in summer, autumn, and spring, respectively) (P < 0.01). An interaction was observed between rainfall and season, then by rainfall between 0 and 100 mm, IRE was shorter (P < 0.05) in winter (6.8 ± 0.3 days), and by rainfall between 100 and 199 mm, IRE was shorter (P < 0.05) in autumn (10.2 ± 0.5 days); however, when rainfall was beyond 200 mm, IRE length was shorter (P < 0.01) in summer (4.8 ± 0.5 days) than in autumn (14.5 ± 0.3 days). The IRE length was also longer in first lambing ewes (P < 0.05) and was not affected by litter size. In the present study, several factors, including the breeding season, rainfall and parity, directly influenced the interval between the male introduction and the onset of estrus by Saint Croix hair sheep.     

Effect of doe milking and supplementation using <Emphasis Type="Italic">Dichrostachys cinerea</Emphasis> pods on kid and doe performance in grazing goats during the dry season

Effects of supplementation and milking of Matebele does four weeks pre-partum to weaning, on milk yield, kid birth weight and growth rate were studied. Forty does were divided into four treatments: supplemented and milked (SM), supplemented and not milked (SNM), not supplemented and milked (NSM); and not supplemented and not milked (NSNM). Supplemented goats were given 200 g/doe/day of Dichrostachys cinerea pods containing 19% CP. The study was carried out in September during time of feed unavailability and animals were grazed on rangelands for seven hours before being given the supplement. Fifty-six kids were born from all the experimental animals and 24 were singles whereas 32 were twins. Milk yield was higher (P < 0.05) in supplemented than non-supplemented does. Although supplementation had no effect on kid birth weights, growth rates were higher (P < 0.05) in the SNM group (103 ± 10.1 g/day) than in the SM group (74 ± 10.8 g/day). Among the non-supplemented groups, kids from milked does had higher (P < 0.05) daily gains (85 ± 10.9 g/day) than those from non-milked does (67 ± 10.7 g/day). Weaning weights were higher (P < 0.05) in SNM does (12.8 ± 1.30 g/day) than in the SM does (10.2 ± 1.17 g/day). Among kids from the non-supplemented does, those from milked does had superior (P < 0.05) weaning weights (11.2 ± 1.23 g/day) than those from non - milked does (9.2 ± 1.27 g/day). Mortalities were also lowest in kids born from SNM does. It is concluded that pre-partum to weaning supplementation generally increases milk production which then increases kids growth rates and weaning weights, as well as reduce kid mortalities.     

Temporal changes in circulating levels of plasma interleukin-8 during peripartum period in Murrah buffaloes (Bubalus bubalis) under subtropical climate

The objective of this study was to elucidate the changes in circulating levels of plasma interleukin-8 (IL-8) during peripartum period in Murrah buffaloes (Bubalus bubalis). IL-8 was estimated in blood plasma of healthy peripartum Murrah buffaloes (n = 6) on days ±30, ±15, ±5, ±3, ±1 and 0 pre- and postpartum with respect to the day of parturition (day 0) in each of the two different seasons (hot–humid and spring). The mean microclimate Temperature–Humidity Index (THI) during spring season was significantly lower (p < 0.01) than the corresponding THI in hot–humid season. In both the seasons, plasma IL-8 remained lower in prepartum period (≤46.56 ± 14.08 pg/ml during spring and ≤ 73.18 ± 18.56 pg/ml during hot–humid season) than in the postpartum period (≥51.41 ± 13.82 pg/ml during spring and ≥ 84.13 ± 16.97 pg/ml in hot humid season). During spring, the IL-8 levels were significantly higher (P < 0.05) on days +5 and +15 postpartum in comparison to the IL-8 levels on days −30, −5, and −3 prepartum. During hot–humid season, IL-8 level was significantly higher (P < 0.05) on day +30 as compared to the IL-8 levels on days −30 and −5 prepartum. The correlation between IL-8 and mean microclimate THI was significant (r = 0.25, P < 0.01). From the results, it is concluded that peripartum period in buffaloes is associated with an inflammatory response leading to significantly higher plasma IL-8 during parturition and postpartum period than in the pre-partum period.     

Growth performance and carcass characteristics of indigenous Mukota pigs of Zimbabwe

Carcass quality characteristics are essential in affecting grading and revenue that pig producers realize. No information is available on the grading of carcasses in indigenous Mukota pigs of Zimbabwe. The objective of this study was to determine the influence of genotype (Mukota and Large White × Mukota) and sex on post-weaning growth performance and carcass traits of pigs fed maize cob-based diets. All pigs were weighed at 2-week intervals to estimate average daily gain, dressing percentage (DP), and carcass lengths. Backfat thickness was also measured. Males had higher body weight gains than females (P < 0.05). Growth rates for Mukota (0.31 ± 0.010) and crossbred (0.41 ± 0.030) pigs were lower in the cool season than the other seasons (P < 0.05). Body weights were consistently higher in the crossbred than in the Mukota pigs (P < 0.05). Mukota pigs showed a peak growth between 12 and 14 weeks post-weaning (P < 0.05). The DPs were 0.70 and 0.73 for the Mukota and crossbred pigs, respectively (P < 0.05). Crossbred pigs had longer (P < 0.05) carcasses than Mukota (655.5 ± 1.68 versus 507.2 ± 0.92 mm). Although there were no differences in the backfat thickness between males and females of the crossbred pigs, Mukota males had thicker backfat than the females (P < 0.05). Crossbreeding is, therefore, significant in improving carcass grades of Mukota pigs.     

Effect of cooking and methionine supplementation on nutritional value of bitter vetch seed as a feed ingredient for broilers

The present study was conducted to evaluate the adequacy of applying heat treatment and methionine (Met) supplementation to improve the use of bitter vetch (BV) as a feed ingredient in the growth diet of broilers. A total of 540 Ross-308 chicks were fed various BV-supplemented diets between the ages of 35 and 49 days. The chicks were assigned randomly to one of nine experimental treatments, including raw and cooked bitter vetch seeds at two levels (100 and 200 g/kg) with or without Met (210 mg/kg) supplement and a corn–soybean-based diet as control. Results showed that feeding the 200-g/kg raw BV decreased feed intake by 52% in relation to the control diet (P < 0.05). Cooking the BV did not improve the feed intake. Met supplementation of 100 g/kg raw or cooked BV and 200 g/kg cooked BV resulted to a similar feed intake in the control group. Chicks fed with the 200 g/kg raw BV had an average depressed body weight gain of 90% in comparison to the birds fed with the control diet. The combination of cooking and Met supplementation of this diet resulted to a similar body weight gain to the control diet. Feeding 100 g/kg of raw or cooked BV also reduced (P < 0.05) body weight gain, and Met supplementation of these diets resulted in a body weight gain similar to the control group. Chicks fed with 100 g/kg of raw or cooked BV supplemented with Met or 200 g/kg of cooked BV plus Met has similar feed conversion ratio to the control group. In conclusion, heating BV seeds is not sufficient to overcome the limiting effects of BV seeds on feed intake and weight gain, and that Met supplementation does provide some improvement. The combination of cooking and Met supplementation was more efficient.     

Effect of protein supplementation on reproductive and productive performance in <Emphasis Type="Italic">Bos indicus</Emphasis> × <Emphasis Type="Italic">Bos taurus</Emphasis> heifers raised in the humid tropics of Costa Rica

In order to evaluate the effect of protein supplementation on the productive and reproductive performance of heifers, 45 Bos indicus × Bos taurus heifers, 673 ± 146 days of age and weighing about 340 kg, were divided into two groups. The control group (n = 23) continued without supplementation, but the supplemented group (SG; n = 22) received concentrate at a rate of 1% BW kg per day. Animals were adapted to the concentrate over a 15-day period and then supplemented for 30 days, after which estrus was synchronized using a progesterone implant. Back fat thickness (BFT) was assessed by ultrasound. The SG had better average daily weight gain than the nonsupplemented group (0.63 ± 0.16 vs. 0.51 ± 0.13 kg/day, P < 0.05) and tended to show a better percentage ovulation (P < 0.10, 77% vs. 57%, respectively). However, this tendency was not reflected in the final pregnancy rates. No differences were observed between groups in dry matter intake and body condition scores. SG with a high BFT (>0.70 cm) showed a better ovulation percentage than those with low BFT (<0.69 cm; P < 0.01). Additionally, the pregnancy rate of supplemented heifers with high BFT tended to be better than heifers with low BFT in this same group (67% vs. 30%, respectively, P < 0.10). It is concluded that protein supplementation improved reproductive performance and that ultrasonography to measure BFT may be used to estimate reproductive performance.     

Relationship of age to body weight,scrotal circumference,testicular ultrasonograms,and semen quality in Sahiwal bulls

The objective of the present study was to determine the relationship of age to body weight (BW), scrotal circumference (SC), number of pixels of testicular ultrasonograms (NP), and semen quality in Sahiwal bulls. The study was based on 128 Sahiwal bulls of different age groups (from 0 to >100 months of age). Bulls were evaluated for SC, BW, and NP. Semen was evaluated once a week for five consecutive weeks from regularly collected donor bulls (n = 86) ranging in age from 25–30 to >100 months. Ejaculate volume, sperm motility, sperm concentration, sperm morphology, percent live sperms, sperm plasma membrane integrity, and normal acrosome were compared among different age groups. Mean SC and BW increased (P < 0.05) in a curvilinear manner from birth to >100 months of age. Mean NP of testicular ultrasonograms increased (P < 0.05) from 0 to 24 months and then plateaued until >100 months of age. Body weight, SC, and NP were positively correlated with age from birth until >100 months (r = 0.91, 0.87, and 0.40, respectively). Ejaculate volume (5.7 ± 0.2 vs. 4.6 ± 0.09 ml) and sperm concentration (1,281.6 ± 17.7 vs. 1,115.8 ± 55.9 × 10⁶/ml) increased (P < 0.05) in mature bulls compared to younger ones. However, motility (68.6 ± 0.3%), plasma membrane integrity (50.8 ± 1.0%), and normal acrosome (74.8 ± 0.5%) remained insignificant due to age. In six of eight age groups studied, morphological abnormalities were well within the range (18.1 ± 0.3%). In conclusion, the BW, SC, and NP of testicular ultrasonograms, ejaculate volume, and concentration increased with age. Moreover, semen quality is fairly independent of age except volume and concentration in Sahiwal bulls.     

Growth performance,carcass characteristics and meat sensory evaluation of West African dwarf sheep fed varying levels of maize and cassava hay

A study was conducted to determine the growth performance and meat yield and quality of West African dwarf sheep. Twenty rams weighing an average of 15.3 ± 0.79 kg live weight and with an average age of 18 months were allotted at random to five dietary treatments of 0%, 25%, 50%, 75% and 100% maize hay (MH) for a period of 105 days. Dry matter (DM) intake and growth rate of the rams were improved as the level of cassava hay (CH) increased in the diets. Live weight gain varied significantly (P < 0.05) across the treatments, ranging from 38.8 to 47.9 g/day. The carcass weight of the rams fed 100% MH was significantly (P < 0.05) lower compared with the other treatments. Dressing percentage ranged from 56.5% to 61.0% with no significant (P > 0.05) difference observed across the treatments, while the distribution of the slaughtered parts was similar (P > 0.05) regardless of the dietary treatment. Proximate composition of the meat from the loin indicated that the DM, crude protein, fat and ash contents were not influenced (P > 0.05) by the dietary treatments. Panellists rated the meat to be similar (P > 0.05) in flavour, juiciness, tenderness and overall acceptability while colour and texture varied significantly (P < 0.05) across the treatments. In conclusion, this study indicated that better growth performance and meat production in West African dwarf sheep can be improved in form of body weight and carcass production when fed 25%MH and 75% CH diet.     

Feed intake and utilization in sheep fed graded levels of dried moringa (<Emphasis Type="Italic">Moringa stenopetala</Emphasis>) leaf as a supplement to Rhodes grass hay

The effects of feeding graded levels of dried moringa (Moringa stenopetala) leaf on intake, body weight gain (BWG), digestibility and nitrogen utilization were studied using male sheep (BW of 13.8 ± 0.12 kg). Six sheep were randomly allocated to each of the four treatment diets: Rhodes grass (Chloris gayana) hay offered ad libitum (T1), hay + 150 g moringa leaf (T2), hay + 300 g moringa leaf (T3), hay + 450 g moringa leaf (T4) were offered daily. A 7-day digestibility trial and an 84-day growth experiments were conducted. Dry matter (DM), organic matter (OM) and crude protein (CP) intakes increased (P < 0.05) with increasing levels of moringa leaf in the diets. Sheep fed T2, T3 and T4 diets gained (P < 0.05) 40.2, 79.1 and 110.1 g/head/day, respectively, while the control group (T1) lost weight (−13.3 g/head/day). The apparent digestibilities of DM, OM, neutral detergent fibre and acid detergent fibre were similar (P > 0.05) among treatments. The digestibility of dietary CP increased (P < 0.05) with increasing levels of moringa leaf, but there was no significant difference between T2 and T3 diets. The nitrogen (N) intake and urinary N excretion increased (P < 0.05) with increasing levels of moringa leaf. The N retention was highest (P < 0.05) for 450 g moringa leaf supplementation. The control group was in a negative N balance. Supplementing a basal diet of Rhodes grass hay with dried moringa leaves improved DM intake, BWG and N retention. It is concluded that M. stenopetala can serve as a protein supplement to low-quality grass during the dry season under smallholder sheep production system.