Effect of feeding protected fat and proteins on milk production,composition and nutrient utilization in Murrah buffaloes (Bubalus bubalis)

Objective of this study was to investigate the effect of feeding protected fat and proteins on milk production, composition and nutrient utilization in Murrah buffaloes (Bubalus bubalis). Eighteen buffaloes were divided into two groups (9 each) on the basis of most probable production ability. Buffaloes in control group (C group; most probable production ability 2204 kg) were fed chaffed wheat straw, chopped maize fodder and concentrate mixture as per requirements. Buffaloes in supplemented group (S group; most probable production ability 2211 kg) were fed same ration as C group plus 2.5% rumen protected fat (on dry matter intake basis) and formaldehyde treated mustard and groundnut oil cake (1.2 g formaldehyde/100 g crude protein) in place of unprotected cakes. Group S buffaloes were supplemented rumen protected fat and protein 60 days pre-partum to 90 days postpartum and persistence of milk production was monitored up to 210 days of lactation. Milk yield during supplementation period (90 days) in S group was 13.11 kg/d and was 19% higher (P<0.01) than the C group (11.01 kg/d), whereas after supplement withdrawal (120 days), it was 11.04 kg/d and was 15% higher (P<0.01) than the C group (9.61 kg/d). There was no effect on total solid, protein, solid-not fat (SNF) and lactose contents in the two groups, whereas milk fat yield was increased (P<0.05) and level of milk urea nitrogen was decreased (P<0.01) in S group. Moreover, the supplement produced noticeable changes in the fatty acid profile of the milk fat, i.e., reduction in the concentration of saturated fatty acids (SFA) by 19% and an increase in that of unsaturated fatty acids (USFA) by 36%. Besides, digestibility of dry matter, crude protein, acid detergent fiber and neutral detergent fiber were not affected, whereas ether extract digestibility was higher (P<0.05) in S group. There was no effect on plasma glucose, non-esterified fatty acids, triglycerides and cholesterol concentrations between two groups, whereas blood urea nitrogen concentration was lower (P<0.01) in S group. Supplementation of protected nutrients to buffaloes increased milk production and unsaturated fatty acids content in milk fat and persistence of lactation after supplements were withdrawn.     

The interaction between lactose level and crude protein concentration on piglet post-weaning performance,nitrogen metabolism,selected faecal microbial populations and faecal volatile fatty acid concentrations

A performance study and a nitrogen balance study (2×3 factorial) were conducted to investigate the interaction between lactose level (215 and 125 g/kg) (lactofeed 70; 860 g whey permeate/kg, 140 g soya bean meal/kg, Volac International, UK) and crude protein (CP) concentration (160, 185 and 210 g/kg) on post-weaning piglet performance, nitrogen metabolism, faecal microbiology and faecal volatile fatty acid concentrations. In the performance trial, 252 piglets (7.6 kg; 33 days of age) were assigned to one of six dietary treatments following a 12-day period on a commercial creep diet (17 MJ/kg DE, 16 g lysine/kg). The experimental diets were fed for 28 days (days 12–40) and were formulated to have identical digestible energy (15 MJ/kg) and total lysine (14.5 g/kg) contents. In the N balance experiment, 24 boars (20 kg live weight) were offered the same diets as in the performance trial. Faecal samples were collected for selected microbial populations. There was an interaction (P<0.05) between lactose and CP concentration in daily gain (ADG) and daily feed intake (ADFI) (P<0.01) during the weaner period (days 12–40). At the high lactose level there was a linear increase in ADG and ADFI with increasing CP. However, at the low lactose level there was no increase in ADG or ADFI above the medium CP. Pigs offered 215 g lactose/kg had a higher dry matter (P<0.001), organic matter (P<0.001), energy (P<0.001), nitrogen (P<0.01) and neutral detergent fibre (P<0.05) coefficient of total tract apparent digestibility compared to pigs offered 125 g lactose/kg. There was an interaction between lactose and CP concentration for nitrogen intake (NI) (P<0.05), urine pH (P<0.05) and selected faecal microbial populations. At the high CP level, pigs offered diets containing 215 g lactose/kg had a higher NI and a lower urine pH than pigs offered 125 g lactose/kg (P<0.05). However, the inclusion of lactose had no significant effect on either NI or urine pH at the low or medium CP concentration. At the low lactose level there was a linear increase in faecal E. coli population and a linear decrease in faecal Lactobacilli population with increasing CP. However at high lactose levels CP concentration had no effect on either E. coli or Lactobacilli populations. Pigs offered 215 g lactose/kg had a significantly higher Bifidobacteria population compared to pigs offered 125 g lactose/kg. There was a linear decrease in Bifidobacteria population as CP increased. In conclusion, at the high lactose level there was a linear increase in ADG and ADFI with increasing CP concentrations. There was no increase in these parameters above 185 g CP/kg at the low lactose level.     

Effects of feeding nutritionally balanced rations on animal productivity,feed conversion efficiency,feed nitrogen use efficiency,rumen microbial protein supply,parasitic load,immunity and enteric methane emissions of milking animals under field conditions

Milking animals produce milk commensurate with their genetic potential only when they are fed a nutritionally balanced ration in an amount that provides nutrients to express their genetic potential. As animals kept by smallholder farmers are rarely fed a balanced ration, a programme to feed balanced rations to animals of such farmers was launched in India. Based on their milk yield, the animals were categorized as: low (<8 kg/d), medium (8–12 kg/d) and high (>12 kg/d) yielders. Milk yield, milk fat and net daily income to milk producers were recorded before and after feeding a balanced ration. Nutritional status of animals showed that, for 71% of animals’, crude protein (CP) and metabolizable energy intakes were higher and, for 65% of animals’, calcium and phosphorus intakes were lower than requirements. Ration balancing improved milk yield by 2–14% and its milk fat proportion by 0.2–15%. Feed conversion efficiency, as kg of fat corrected milk (FCM)/kg of dry matter intake of buffaloes (n = 1131) before and after feeding balanced rations was 0.6 and 0.7, respectively, and in cows (n = 540) the values were 0.6 and 0.8. Dietary N secreted into milk increased from 0.16 to 0.25 and 0.16 to 0.19 in low and medium yielding cows and buffaloes, respectively. Rumen microbial CP synthesis also increased (P<0.05) by 36 and 38% in cows and buffaloes, respectively. On feeding balanced rations, levels (mg/ml) of plasma immunoglobulins IgG, IgM and IgA increased from 14.48 to 22.11, 2.69 to 3.29 and 0.48 to 0.67, and the parasitic load was reduced from 168 to 81 eggs/g of faeces. Enteric CH₄ emissions (g/kg milk yield) was reduced by 15–20% (P<0.05) in these lactating animals. Results demonstrate that feeding nutritionally balanced rations increased milk production and reduced enteric CH₄ emissions and N excretion from lactating cows and buffaloes. While implementation of a ration balancing programme under small holding systems is challenging, large scale use of this programme in tropical countries can help improve productivity of milking animals with available feed resources in an environmentally sustainable manner.     

Dietary supplementation with maize distillers dried grains with solubles during late gestation and lactation: Effects on sow and litter performance,and on colostrum and milk composition

The objectives of this study were to determine the effects of maize distillers dried grains with solubles (DDGS) during late gestation and lactation on sow and piglet performance, and on colostrum and milk composition. Thirty-six second- and third-parity (2.43 parity) sows (Yorkshire) were allotted to 1 of 3 groups and fed diets containing 0 (control), 200 or 400 g DDGS/kg during the last 20 d of gestation and throughout a 21 d of lactation. Experimental diets contained 12.9 MJ metabolizable energy/kg and 9.7 g lysine/kg. The colostrum and milk samples were obtained on d 0 (farrowing) and d 21 (weaning). There were no differences (P>0.05) in the sows’ average gestation lengths, weaning-to-estrus interval, average daily feed intake, and the lactation backfat and body weight change between dietary treatments. There were no dietary effects (P>0.05) of DDGS on the numbers of total, born alive piglets, average birth weights, piglets per litter at weaning or piglets average daily gain during lactation. No differences (P>0.05) were observed in total solids, protein, fat and lactose among the sows fed the DDGS diets compared with the control. The composition of total solids and protein of sows colostrum and milk were higher at farrowing (d 0) than at weaning (d 21) (P<0.001). However, the fat and lactose content of sows colostrum and milk were increased (P<0.001) from d 0 (farrowing) to d 21 (weaning). In conclusion, the results suggest that 400 g DDGS/kg (87 g lysine/kg) supplemented with 5.2 g lysine/kg included in late gestation and lactation diets is sufficient to replace all the dietary soybean meal without significantly affecting sow and litter performance or colostrum and milk composition.     

Characteristics of Korean-Saanen goat milk caseins and somatic cell counts in comparison with Holstein cow milk counterparts

Characteristics of α- and β-casein fractions in the milk of Korean-Saanen goats were compared with those of Holstein cow milk using capillary electrophoresis (CE) analysis. The αs₁-CN content of the Saanen goat milk samples varied from 2.4% to 9.3% of total proteins. Total αs-CN content of the goat milk varied from 10.1% to 17.0%. Total β-CN content containing β₁-CN and the β₂-CN varied from 49.6% to 61.0% of total proteins. Average αs-CN to β-CN ratio of the Saanen goat milk from different farms was 0.24 ± 0.04, ranging from 0.17 to 0.33. The αs-CN (αs₁-CN + αs₀-CN) to β-CN (β_A1-CN + β_A2-CN) ratio of Holstein cow milk was 0.81, which was much higher than that of Korean-Saanen goat milk. The goat milk samples having more than 1.5 million cells/ml somatic cell counts (SCC) contained higher αs-CNs (P < 0.01) and lower β-CNs (P < 0.05) contents than milks with <1.5 million SCC. This resulted in a higher αs-CN to β-CN ratio (P < 0.01) in the milk with >1.5 million SCC.     

The effect of machine or hand milking on milk production,composition and SCC in mountainous Greek breed (Boutsiko) ewes

The aim of this work was to determine the effect of two different milking methods (machine versus hand milking) on milk yield, milk composition and somatic cell counts (SCC) in mountainous Greek Boutsiko ewes. Ninety-six ewes were divided in two groups of 48 ewes each. Milk yield, lactation number (parity) and type of lambing were taken into consideration for the separation of the ewes. One group was milked by machine and the other by hand. Milk production, milk composition (with Milkoscan 104) and SCC (with Fossomatic) were performed every 14 days, in the morning and evening milking; during the experimental period seven samplings were performed in total. The results of this study have shown that ewes milked by machine gave a greater daily milk yield as compared to those milked by hand (698 ml versus 652 ml; P < 0,05) and less log SCC (5.37 versus 5.62; P < 0,05). The composition of milk did not differ between the two treatments. Also, no phenotypic correlations were established between SCC and milk production or composition, apart from a negative correlation, which was noted between SCC and the percentage of lactose. The results of this experiment have shown that ewes of the Boutsiko breed can be milked by machine without any problems.     

The influence of dry period feeding on liver fat and postpartum performance of dairy cows

Animal performances were monitored in 30 Friesean dry cows (18 multiparous, MP-cows and 12 primiparous, PP-cows) starting six weeks before calving to eight weeks after calving. The cows were kept indoors and fed individually with a prepartum diet containing either low, moderate or high energy (0.75, 1.00 or 1.25 of the calculated ME requirement) and supplemented with low (0.3 kg day⁻¹) or high (1.5 kg day⁻¹) rapeseed meal (RSM). The diets were consisted of 1.5 kg hay, 20–25 kg wilted grass silage and grain (barley and oat, 1 : 1 DM basis) with RSM. The average ME intake during six weeks of prepartum was 75, 97 and 123 MJ day⁻¹ on three different energy levels. After calving the cows were fed grass silage ad lib, 6.5 kg (primiparous) or 8.5 kg (multiparous) grain and 1.5 kg RSM. Liver biopsy and blood samples were taken to determine differences in metabolites due to diet and parity. Reduction of prepartum energy allowance to 0.75 of the moderate level did not affect the calf's birth weight and colostrum composition. Cows fed prepartum low energy–high rapeseed meal diet (LEHR) showed a faster increase in feed intake and milk production after parturition. Continuous low feed intake and milk production were observed in cows fed a prepartum high energy–low rapeseed meal diet (HELR). Milk yield was constantly lower for cows fed prepartum high energy diet, the difference being significant (p<0.01 and p<0.05) at six and seven weeks of lactation. Overall milk yield also showed a linear decrease with energy feeding level and an increase (p<0.10) with RSM feeding levels. Prepartum high energy feeding increased (p<0.01) milk protein content. Neither energy nor RSM feeding level affected the liver fat infiltration of the experimental cows. Cow parity however showed a significant influence on liver fat content, β-hydroxybutyrate (BHBA) and plasma glucose. A week before calving, the plasma concentration of essential amino acids (EAA) was lower for cows fed prepartum low energy diet. During the first four weeks of lactation, the concentrations of plasma non-esterified fatty acids (NEFA) and insulin were similar for all the treatment group.     

Effect of elemental nano-selenium on feed digestibility,rumen fermentation,and purine derivatives in sheep

The objective of this experiment was to study the effect of elemental nano-selenium (NS) on feed digestibility, rumen fermentation, and urinary purine derivatives in sheep. Eight male ruminally cannulated sheep (42.5 ± 3.2 kg of body weight, BW) were used in a replicated 4×4 Latin square experiment in four 20 day periods. Depending on treatment designation, sheep were fed the basal diet supplemented with 0 (control), 0.3, 3 and 6 g of nano-Se/kg dry matter (DM). Ruminal pH (range of 6.68–6.80) and ammonia N concentration (range of 9.95–12.49 mg/100 mL) was decreased (P<0.01), and total VFA concentration (range of 73.63–77.72 mM) was increased linearly (P<0.01) and quadratically (P<0.01) with increasing nano-Se supplementation. The ratio of acetate to propionate was linearly (P<0.01) and quadratically (P<0.01) decreased due to the increasing of propionate concentration. In situ ruminal neutral detergent fiber (aNDF) degradation of Leymus chinensis and crude protein (CP) of soybean meal were linearly (P<0.01) and quadratically (P<0.01) improved by feeding nano-Se. Similarly, nutrients digestibility in the total tract and urinary excretion of purine derivatives were also quadratically (P<0.01) changed by increasing nano-Se supplementation. The present results indicated that nano-Se supplementation in basal diet improved rumen fermentation and feed utilization. Nano-Se could also stimulate rumen microbial activity, digestive microorganisms or enzyme activity. The optimum dose of nano-Se was about 3.0 g/kg dietary DM in sheep.     

Effects of dietary forage-to-concentrate ratios on performance and carcass characteristics of growing fat-tailed lambs

This study was conducted to evaluate the effects of using different dietary forage-to-concentrate ratios on growth performance and carcass characteristics of eighty Chall male fat-tailed lambs, averaging 165 ± 15 (SD) days of age and body weight of 38.4 ± 4.8 (SD) kg, randomly assigned to four diets containing alfalfa hay-to-concentrate ratios (DM basis) of 70:30 (C30), 50:50 (C50), 30:70 (C70), 10:90 (C90). Metabolizable energy (ME) contents were, 9.12. 9.96, 10.67, and 11.34 MJ/kg dry matter (DM) and crude protein (CP) contents were 143, 152, 161, and 174 g/kg for the C30, C50, C70, and C90 diets, respectively. Sixteen lambs (4 lambs/treatment) were slaughtered at the end of feeding period (84 days). Dry matter intake and feed conversion ratio (FCR) (i.e., kg DM/kg gain) decreased linearly (P<0.001) as concentrate level increased in the diet. However, a linear increase (P<0.001) for ME intake and a quadratic increase for average daily gain (ADG, P<0.001) and final body weight (P<0.01) were observed with increasing dietary concentrate. Slaughter weight, eye muscle area, and weights of lean, bone, neck, shoulder, rack–loin, leg, skin, head, lung, and spleen were not affected by the experimental diets. However, as dietary concentrate increased, a linear increase for dressing percentage, feet weight (P<0.001), and backfat thickness (P<0.02), a quadratic increase for empty body weight (EBW, P<0.02), weights of hot and cold carcass (P<0.001), subcutaneous fat (P<0.02), total fat (P<0.01), brisket–flank (P<0.04), and tail fat (P<0.001), a linear decrease for weights of liver (P<0.01), and heart (P<0.05), and a quadratic decrease for lean-to-fat ratio (P<0.02) were observed. This study indicates that in Chall fat-tailed lambs the increase of dietary concentrate (up to 700 g/kg) improves growth rate, FCR and dressing percentage with negative effect on carcass lean-to-fat ratio.     

Effect of feeding Rumen-protected capsule containing niacin,K2SO4, vitamin C,and gamma-aminobutyric acid on heat stress and performance of dairy cows

This study was conducted to evaluate the effects of supplemental rumen-protected capsule (RPC) on animal performance, serological indicators, and serum heat shock protein 70 (HSP70) of lactating Holstein cows under heat stress (HS). During summer months, 30 healthy multiparous lactating Holstein cows with a parity number of 3.1 ± 0.44, 70 ± 15 d in milk, an average body weight of 622 ± 62 kg, and an average milk yield of 32.28 ± 0.96 kg/d, were used. The cows were randomly allocated to two groups: a control group and an RPC-supplemented group (0.13373 kg K₂SO₄, 0.02488 kg vitamin C, 0.021148 kg niacin, and 0.044784 kg gamma-aminobutyric acid per cow). During the 42-d experiment, ambient air temperature and relative humidity inside and outside the barn were recorded hourly every day for the determination of temperature-humidity index (THI). Milk and blood samples were collected every week, and body weight and body condition scoring were measured on day 0. Based on the THI values, the animals had moderate HS. On day 42, the RPC group had lower HSP70, adrenocorticotropic hormone (P = 0.0001), lactate dehydrogenase (P = 0.0338), and IL-6 (P = 0.0724) levels than the control group, with no significant differences in creatine kinase, glucocorticoid, or IL-2 levels. Milk yield, energy-corrected milk, and dry matter intake were higher in RPC than in the control group (P = 0.0196). There were no significant differences in milk fat or daily protein levels between the two groups; however, daily protein and milk fat levels were higher in the RPC group than in the control group (P = 0.0114 and P = 0.0665, respectively). Somatic cell counts were no different between the two groups. In conclusion, RPC may alleviate HS and improve dairy cow performance.     

Effects of untreated and heat-treated canola presscake on milk yield and composition of dairy cows

Five primiparous and five multiparous Holstein cows were used in two Latin square design experiments to determine effects of feeding unheated and heated canola presscake on milk yield and composition, and milk fatty acid concentrations of lactating dairy cows. Five diets that differed in level and source of dietary fat were formulated: a low fat control diet with 30 g kg⁻¹ fat from tallow, an unheated canola presscake supplemented diet (50 g kg⁻¹ fat), a heated canola presscake supplemented diet (50 g kg⁻¹ fat), a high tallow plus unheated canola meal supplemented diet (50 g kg⁻¹ fat), and a high tallow plus heated canola meal supplemented diet (50 g kg⁻¹ fat). In sacco ruminal degradability of heated and unheated canola presscake was compared with that of heated and unheated canola meal in a randomized complete block design using two ruminally fistulated cows. Heat treatment reduced ruminal DM and CP degradability of canola presscake. Multiparous cows fed diets supplemented with heated or unheated canola presscake produced more milk than those fed diets containing similar levels of fat from tallow with heated or unheated canola meal, respectively. High levels of fat from any diet reduced milk fat percentage for cows of either parity. Feeding heated canola products increased milk and milk protein yields in primiparous cows only, but cows of both parities fed diets containing canola presscake produced milk with lower concentrations of C12:0, C14:0, and C16:0 fatty acids than cows fed the canola meal and tallow diets, although concentrations of C18:1 n-9 were unaffected by fat source or level. Feeding canola products to dairy cows can alter milk fatty acid profile, but only primiparous cows have increased productivity as a result of feeding heated, versus unheated, canola presscake.     

Plasma prolactin,blood metabolites and milk production in bromocryptine-treated crossbred goats

To determine the effect of bromocryptine on plasma prolactin, metabolites and milk production, six healthy crossbred goats in their second or third lactation were selected from the institute’s goat herd. The goats were injected with bromocryptine @ 5 mg per day intramuscularly for a period of 5 days during 55–60 days of lactation (period I) and treatment was repeated after 14 days for an additional 5 days (period II). Blood samples were collected for 5 consecutive days before, during and after administration of bromocryptine during both periods of the study. Milk samples were collected on days coinciding with the days of blood sampling. During period I, bromocryptine administration decreased (P < 0.01) milk yields by 27.4%. After withdrawal of bromocryptine the yields increased (P < 0.01); however, during period II, bromocryptine treatment did not decrease milk yields. During period I bromocryptine treatment suppressed prolactin level (P < 0.01) which coincided with decrease in milk yield, but in period II such decreases in prolactin did not coincide with changes in milk yields. Fat content increased (P < 0.01) after bromocryptine administration in both periods. A decrease (P < 0.01) in protein and lactose content indicated a possible role of prolactin in the synthesis of these constituents by the mammary gland cell in goats. Blood glucose and NEFA were not affected by bromocryptine in period I but in period II an increase in blood glucose with a simultaneous decrease in NEFA was observed (P < 0.01).From this study it is concluded that prolactin has a role in the maintenance of milk secretion through protein synthesis by the mammary gland. However, it does not seem to have any direct role on milk fat synthesis.     

Variation in blood leucocytes,somatic cell count,yield and composition of milk of crossbred goats

Ten multiparous crossbred goats, five each of alpine × beetal (AB) and saanen × beetal (SB) were selected from the National Dairy Research Institute goat herd immediately after parturition. These were managed as per the practices followed in the institute’s goatherd. Blood and milk samples were collected at biweekly intervals from day 14 post-kidding for 22 weeks (154 days). Somatic cell count, electrical conductivity, fat, protein and lactose contents of milk were determined using standard methods. In the blood samples total leucocytes and differential leucocytes were also determined. Somatic cell counts were high immediately after parturition on day 14 of lactation and declined gradually with advanced lactation. There were individual variations (P < 0.01) in somatic cell counts between different lactation periods. Somatic cell count of milk was negatively correlated with neutrophils only (P < 0.05) and was neither correlated with milk yield, or with fat, protein, lactose content of milk. Electrical conductivity of milk was low up to four weeks of lactation and thereafter increased as the lactation advanced. Lactose content of milk declined gradually with the advancement of lactation. Fat content of milk was stable up to the eighth week and thereafter increased with advancement of lactation while the protein content of milk did not change significantly during lactation.     

Thermoregulatory responses of Holstein cows exposed to experimentally induced heat stress

Heat stress (HS) adversely influences productivity and welfare of dairy cattle. We hypothesized that the thermoregulatory mechanisms vary depending on the exposure time to HS, with a cumulative effect on the adaptive responses and thermal strain of the cow. To identify the effect of HS on adaptive thermoregulatory mechanisms and predictors of caloric balance, Holstein cows were housed in climate chambers and randomly distributed into thermoneutral (TN; n=12) or HS (n=12) treatments for 16 days. Vaginal temperature (VT), rectal temperature (Tre), respiratory rate (RR), heart rate (HR), and dry matter intake (DMI) were measured. The temperature and humidity under TN were 25.9±0.2 °C and 73.0±0.8%, respectively, and under HS were 36.3±0.3 °C and 60.9±0.9%, respectively. The RR of the HS cows increased immediately after exposure to heat and was higher (76.02±1.70bpm, p<0.001) than in the TN (39.70±0.71bpm). An increase in Tre (39.87±0.07 °C in the HS vs. 38.56±0.03 °C in the TN, p<0.001) and in VT (39.82±0.10 °C in the HS vs. 38.26±0.03 °C in the TN, p<0.001) followed the increase in RR. A decrease (p<0.05) in HR occurred in the HS (62.13±0.99bpm) compared with the TN (66.23±0.79bpm); however, the magnitude of the differences was not the same over time. The DMI was lower in HS cows from the third day (8.27±0.33 kg d⁻¹ in the HS vs. 14.03±0.29 kg d⁻¹ in the TN, p<0.001), and the reduction of DMI was strongly affected (r=−0.65) by changes in the temperature humidity index. The effect of environmental variables from the previous day on physiological parameters and DMI was more important than the immediate effect, and ambient temperature represented the most determinant factor for heat exchange. The difference in the responses to acute and chronic exposure to HS suggests an adaptive response. Thus, intense thermal stress strongly influence thermoregulatory mechanisms and the acclimation process depend critically on heat exposure time.     

Nutritional characterization of Mucuna pruriens: 3. Effect of replacing soybean meal with Mucuna on intake,digestibility, N balance and microbial protein synthesis in sheep

Mucuna pruriens seeds have relatively high crude protein (CP) concentrations, but little is known about their potential to replace commonly used CP supplements in ruminant rations. The aim of this experiment was to determine effects of replacing soybean meal (SB) with Mucuna on the performance of lambs. Forty Rambouillet lambs (33.2 ± 5.73 kg) fed a basal diet of maize grain, cottonseed hulls and urea were randomly assigned to one of four supplements formulated by substituting 0 (SB), 330 (Lo), 670 (Med) or 1000 g/kg (Hi) of soybean meal with rolled Mucuna seeds. Lambs were housed individually in metabolic crates and allowed ad libitum access to isocaloric (metabolizable energy=11.7 MJ/kg dry matter, DM) and isonitrogenous (CP = 146 g/kg, DM) diets for 14 d of adaptation and 7 d of total fecal collection. Fecal egg counts and coccidian oocyst scores were determined on d 14. Dry matter intake (1.7 kg/d versus 1.5 kg/d; P<0.05), CP digestibility (774 g/kg versus 714 g/kg DM; P<0.05) and N retention (28.0 g/d versus 20.4 g/d; P<0.01) were higher and amylase-pretreated neutral detergent fiber digestibility (617 g/kg versus 686 g/kg DM) was lower (P<0.05) in sheep fed SB versus Mucuna diets. However, supplementary protein source did not affect rumen pH, blood urea N or glucose concentration, or fecal egg counts. Increasing the level of Mucuna supplementation increased (P<0.05) level and efficiency of microbial protein synthesis, ruminal fluid acidity, total volatile fatty acid concentration, decreased (P<0.05) coccidian oocyst scores, and tended (P<0.10) to increase N retention. Therefore, SB is a better supplement than Mucuna to support performance of lambs. Nevertheless, Mucuna seeds are a promising CP supplement for situations where cost or availability precludes use of SB in ruminant rations.     

Supplementation of isonitrogenous oil seed cakes in cactus (Opuntia ficus-indica)–tef straw (Eragrostis tef) based feeding of Tigray Highland sheep

The experiment was conducted at Maichew Agricultural Technical Vocational Education and Training College, Ethiopia. Twenty four male yearling Tigray Highland sheep with mean body weight (BW) of 21 ± 2.6 kg (mean ± S.D.) were used to investigate the effect of different protein sources on feed intake, nutrient digestibility, BW change and carcass parameters in a study comprising of 90 days feeding trial, followed by 7 days of digestibility trial and evaluation of carcass parameters. Six individually fed animals were used per treatment in a randomized complete block design. The treatments consisted of ad libitum feeding of tef (Eragrostis tef) straw plus 172 g dry matter (DM) of cactus (Opuntia ficus-indica) pear (T1, control) and supplementation with 145 g DM cotton seed cake (CSC) (T2), 195 g DM noug seed cake (NSC) (T3) or 149 g DM peanut cake (PNC) (T4) per head per day. The quantity of the supplements was set to supply 62.5 g crude protein (CP). Tef straw DM intake was depressed (P<0.01) as the result of NSC supplementation. Sheep supplemented with CSC and PNC had higher (P<0.001) total DM intake than the control and NSC supplemented ones. Supplementation with NSC and PNC also resulted in higher (P<0.01) apparent digestibility of DM and OM compared to the control treatment. Supplementation with CSC and PNC resulted in better daily BW gain (P<0.001), feed conversion efficiency (FCE) and dressed carcass weight (P<0.01) compared to the non-supplemented diet. Dressing percentage on slaughter weight base was higher (P<0.01) in supplemented sheep than in the non-supplemented ones. Supplementation with PNC also promoted higher (P<0.05) rib-eye muscle area than in the non-supplemented ones. It was concluded that supplementation with 145 g DM CSC and 149 g DM PNC resulted in better feed intake, BW gain and carcass traits in cactus–tef straw based feeding of sheep.     

Effects of dietary conjugated linoleic acid on metabolic status,BW and expression of genes related to lipid metabolism in adipose tissue of dairy cows during peripartum

Conjugated linoleic acid (CLA) dietary supplementation reduces milk fat content and yield, but its effects on lipid metabolism and energy status remain controversial. The objective of this study was to investigate the effects of dietary CLA on adipose tissue (AT) mRNA abundance of genes related to lipid metabolism, plasma indicators of metabolic status, body condition score (BCS) and BW changes in dairy cows. Sixteen multiparous Holstein cows (3.2 ± 1.4 lactations, 615 ± 15 kg BW) were randomly assigned to treatments: 1) CLA; rumen-protected CLA (75 g/d) or 2) Control; equivalent amount of rumen inert fatty acid (FA) as the previous diet (78 g/d), from − 20.2 ± 3.2 (mean ± SEM) to 21 d relative to calving (d 0). Subcutaneous AT was biopsied from the tail-head region at d 21 to determine the mRNA abundance of genes related to lipid metabolism. Blood samples were collected at − 20.2 ± 3.2, 0, 7, 14 and 21 d relative to calving to determine plasma non-esterified fatty acids (NEFA), beta-hydroxybutyrate (BHBA), insulin and glucose. Conjugated linoleic acid decreased milk fat yield and milk fat content by 15 and 16%, respectively. Cows fed CLA had lower plasma NEFA and BHBA and greater glucose and insulin concentrations (P < 0.05). Mean BCS at 21 d postpartum was greater (P < 0.01; 2.89 vs 2.25), and BCS loss from the day of enrollment to 21 d postpartum was reduced (P < 0.01; − 0.13 vs − 0.64) in the CLA group. The expression of acylcoenzyme A oxidase, carnitine palmitoyltransferase 1A, hormone-sensitive lipase, β2 adrenergic receptor and acetyl-CoA carboxylase was downregulated by CLA supplementation, whereas the expression of sterol regulatory element binding protein, lipoprotein lipase and peroxisome proliferator-activated receptor gamma was upregulated (P < 0.01). In summary, CLA-supplemented cows showed signs of better metabolic status and less severe fat mobilization. Moreover, CLA increased mRNA abundance of genes related to lipogenesis and decreased mRNA abundance of genes related to FA oxidation and lipolysis in the AT of dairy cows during early lactation.     

Designing better water troughs: 2. Surface area and height,but not depth,influence dairy cows’ preference

Water consumption affects milk production of dairy cows. In a previous study, we found that dairy cows preferred to drink from larger than from smaller troughs and that intake was higher when water was offered in the larger, preferred troughs. In this study, we investigated some of the trough's characteristics that may underlie such preference. The volume of water consumed, time spent drinking and number of sips taken by cows (n = 18) were compared when water was offered in two troughs differing in surface area (1.13 m² or 0.28 m²; experiment 1), height (30 cm or 60 cm; experiment 2) or depth (30 cm or 60 cm; experiment 3). In each experiment, each cow was tested individually for six consecutive days with the troughs randomly placed in each side. In experiment 1, cows took more sips (P < 0.01), spent more time drinking (P < 0.01) and drank more water (P < 0.01) from the trough with larger surface area. In experiment 2, cows took more sips from the higher than from the lower trough (P < 0.02) and showed a tendency to consume more water (P = 0.08) and to spend more time drinking (P = 0.08) from the higher than from the lower trough. Trough depth did not influence any of the variables recorded.     

Thermotolerance,health profile and cellular expression of HSP90AB1 in Nguni and Boran cows raised on natural pastures under tropical conditions

Boran (n=15) and Nguni (n=15) cows were used in a study to determine the effect of breed, age and coat colour on the concentration of heat shock protein 90 (HSP90AB1), physiological rectal and skin temperature, and markers of health. The cows were exposed to summer heat stress and Boran cows had higher significant (P<0.05) skin temperature (35.1±0.42 °C) as compared to the Nguni cows (36.0±0.38 °C). Nguni cows had higher body thermal gradients than the Boran cows. Boran cows had thicker skin (P<0.05) and longer hairs (24.3±2.26 mm) than their Nguni counterparts (20.2±2.00 mm). The HSP90AB1 concentration was increased in Boran cows, although breed had no significant (P>0.05) influence. Significantly (P<0.05) high urea and total cholesterol was recorded in Boran cows. Coat colour had a significant (P<0.05) effect on the weight and rectal temperature of the study animals. Coat colour and age had no significant effect (P>0.05) on the concentration of HSP90AB1, although older cows (≥9 years) had higher concentrations (5.4±1.29 ng/ml). Age had a significant (P<0.05) effect on packed cell volume, neutrophil/lymphocyte, urea, total protein and gamma-glutamyl transferase whereas cows with ≥9 years had more concentrations than young ones. Age significantly (P<0.05) influenced hair length, skin temperature and the thermal gradients. Breed was positively correlated (P<0.001) to coat colour, age, body condition score, weight and temperature humidity index while negatively correlated to urea and total cholesterol. It was concluded that Nguni cows were more adaptable to hot environments than the Boran cows as the latter were unable to balance thermal load between their bodies and the environment.     

Effect of grazing and homeopathy on milk production and immunity of Merino derived ewes

The effect of grazing and homeopathic therapy on sheep immune response and milk production was investigated on 40 multiparous Merino derived ewes. Twenty animals were housed in an indoor-bedded pen (P), whereas 20 others were allowed to graze on pasture for 9 h/d (G). P and G animals were fed an equivalent diet in terms of dry matter intake, crude protein percentage and energy concentration. In each group, 10 animals were subjected to unicistic homeopathic treatments (H), while 10 ewes were kept as a control and treated with conventional medicine when necessary (C). The grazing rearing system had a marked positive effect on in vivo cellular immune response (delayed-type hypersensivity to PHA, P < 0.001). Grazing animals produced more milk than the penned ones (1048.00 ± 75.61 kg versus 853.04 ± 67.78 kg, P < 0.05), with increased content of milk fat (7.69 ± 0.15% versus 7.25 ± 0.14%, P < 0.05). Accordingly, blood levels of triglycerides (P < 0.01), urea (P < 0.001) and alanine aminotransferase (ALT) (P < 0.001) were significantly higher in group G. The homeopathic treatments produced limited effects on the milk production and immune response. However, such treatments reduced the risk of contamination of the products with medicinal traces, as H group received no allopathic treatment.