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.     

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.     

Effect of concentrate supplementation levels on growth and slaughter characteristics of SEA and SEA × Norwegian goats under on-farm conditions

A 2?×?3 factorial experiment was carried out to evaluate the effect of goat genotypes and different concentrate levels on growth and slaughter characteristics of Small East African × Norwegian crossbred (SEA × N) and Small East African (SEA) goats. The three concentrate levels were T0 (no access to concentrate), T66 (66 % access to ad libitum concentrate allowance) and T100 (100 % access to ad libitum concentrate allowance). Twenty-four castrated goats of each genotype (18 months old with an average weight of 16.7?±?0.54 kg) were randomly allotted into T0, T66 and T100 treatments. Daily feed intake and fortnight body weight measurements were recorded for the whole 84-day experimental period, after which the animals were slaughtered. Feed intake of T100 animals was 536 g/day, which was 183 g/day higher than that of the T66 group. Supplemented goats (T66 and T100) had significantly (P?<?0.05) higher daily gain and body condition score, and better feed conversion efficiency and dressing percentage than T0 goats. The SEA goats had higher (P?<?0.05) hot carcass weight (8.2 vs. 7.9 kg) and showed better (P?<?0.05) dressing percentage than SEA × N animals. Among supplemented goats, the cost of a 1-kg gain under T66 was Tshs 213/= cheaper than T100 (US$1?≈?Tshs 1,500). It is concluded that goats should be grazed and supplemented with 353 g concentrate/day for satisfactory fattening performance and higher economic return on investment.     

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.     

Intake, live animal scores/measurements and carcass composition and value of late-maturing beef and dairy breeds

The objectives of this study were to compare the progeny of 1) late-maturing beef with dairy breeds and 2) Charolais (CH), Limousin (LM), Simmental (SM) and Belgian Blue (BB) sires bred to beef suckler dams, for feed intake, blood hormones and metabolites, live animal measurements, carcass traits and carcass value in bull and steer production systems. The bull system included 50 late-maturing beef breeds and 22 Holsteins (HO) slaughtered at approximately 15 months of age, whereas the steer system consisted of 56 late-maturing beef breeds and 23 British Friesians (FR) slaughtered at approximately 24 months of age. Beef breeds were suckled until approximately 8 months of age, while dairy breeds were artificially reared until weaning at approximately 3 months of age. All animals were finished on an ad libitum concentrate diet. Mean live weight, live weight gain, carcass gain and feed efficiency were greater (P < 0.05) in beef than dairy breeds in both systems during the finishing period when offered concentrates. Although there was no difference in feed intake between beef and dairy breeds, intake expressed relative to live weight was lower (P < 0.001) in beef breeds in both systems. At 10 months of age and pre-slaughter, beef breeds had higher (P < 0.001) muscularity scores and greater scanned muscle depth (P < 0.001) than their dairy contemporaries. Carcass weight, kill-out proportion, carcass conformation score, meat proportion and value were greater (P < 0.001) and carcass fat and bone proportions were lower (P < 0.05) in beef than dairy breeds in both systems. Insulin concentrations were lower (P < 0.001) in beef than dairy breeds, whereas there was no difference in blood metabolites or IGF-1 concentrations. Feed intake expressed relative to live weight or feed efficiency did not differ between CH, LM, SM or BB sired progeny. Muscularity scores were greater (P < 0.05) in BB than SM, whereas skeletal scores were lower (P < 0.05) in LM than SM. Limousin had lower (P < 0.05) carcass gain per day of age than CH and SM, whereas SM had a lower (P < 0.05) carcass conformation score than BB and CH and a higher (P < 0.05) carcass fat score than CH. Simmental had a lower (P < 0.05) carcass meat proportion and a higher (P < 0.05) carcass fat proportion than CH, LM and BB, which were similar (P > 0.05). The improvement obtained for beef over dairy breeds in live weight gain was 12%, while the improvements in carcass gain and meat produced was 24% and 33%, respectively. This demonstrates that the importance of carcass data contributing to breed comparison studies cannot be over-emphasised.     

Beef heifer production as affected by indoor feed intensity and slaughter age when grazing semi-natural grasslands in summer

Only limited knowledge exists on how to produce high-quality beef carcasses when the cattle also are grazing semi-natural grasslands for nature conservation purposes. The objectives of the two factorially-designed trials were to determine the effects of indoor feed intensity (low vs. high) and slaughter age (18 vs. 22 months) on performance and carcass quality of beef heifers, raised from weaning until slaughter and grazing semi-natural grasslands during growing seasons. In the first trial, 56 Charolais heifers were used of which 28 were fed only grass-clover silage ad libitum (low; CL), and another 28 heifers were fed 2.0 kg of grain daily in addition to the silage (high; CH). In the second trial, 28 Angus heifers were fed grass-clover silage at 80% ad libitum (low; AL), whereas another 28 heifers were fed silage ad libitum (high; AH). According to a national nature conservation score, the grazing pressure on the semi-natural grassland was classified as having been satisfactory to maintain the floristic diversity as no litter had been accumulated onto the sward. From weaning until slaughter, no difference in average daily gains (ADG) was found between the CH and the CL, whereas the AH had higher ADG than the AL (693 vs. 573 g, P < 0.001). Heifers in both trials had higher carcass weights and more fat, Charolais heifers also had better conformation and Angus heifers had higher dressing percentage at 22 months than at 18 months of slaughter age (P < 0.05). In conclusion, carcass traits in both trials were more affected by slaughter age than by feed intensity and desirable grazing effects were achieved on the pasture.     

Effects of replacing grass silage harvested at two maturity stages with maize silage in the ration upon the intake, digestibility and N retention in wether sheep

The objective of this experiment was to study the effects of interactions between medium quality grass silage (GS1) and maize silage (MS) as well as between low-quality grass silage (GS2) and MS on ad libitum intake, digestibility and N retention in wether sheep. Two grass silages (GS1 and GS2) were ensiled in round bales, without additives, from the primary growth of orchard grass (Dactylis glomerata L.) harvested at two different maturity stages. The study consisted of seven feeding treatments incorporating GS1, GS2 and MS fed alone and forage mixtures of GS1 and MS as well as GS2 and MS (67:33% and 33:67%, respectively, DM (dry matter) basis).Delayed harvesting lowered (P < 0.05) the crude protein (CP) concentration in GS2 compared to GS1. The DM content (g kg^− 1 fresh sample) and starch concentration (g kg^− 1 DM) of MS were 264 and 211, respectively.Inclusion of MS in the GS1-based ration had positive linear effects on CP and starch digestibility (P < 0.05 and P < 0.01, respectively) and N intake (P < 0.01) while a negative effect on neutral detergent fibre (NDF) and acid detergent fibre (ADF) digestibility (P < 0.05 and P < 0.01, respectively). A positive associative response of GS1 and MS was observed for DM ad libitum intake (g kg^− 1 M^0.75 day^− 1) (quadratic, P < 0.05), CP digestibility (quadratic, P < 0.01), N intake (quadratic, P < 0.01) and N balance (quadratic, P < 0.05). Inclusion of MS into the GS2-based ration had a positive linear effect on the ration fresh matter ad libitum intake (kg day^− 1 and g kg^− 1 M^0.75 day^− 1) (P < 0.01 and P < 0.001, respectively), NDF ad libitum intake (kg day^− 1 and g kg^− 1 M^0.75 day^− 1) (P < 0.01), digestibility of DM (P < 0.01), organic matter (OM) (P < 0.01), ADF (P < 0.05), starch (P < 0.001), digestibility of OM in DM (D-value) (P < 0.001), and N intake (P < 0.01). Positive associative effects of GS2 and MS were observed on all the intake and digestibility parameters measured, N intake (quadratic, P < 0.001) and N balance (quadratic, P < 0.05). It was concluded that, as expected, a positive associative response of GS2 and MS was recorded for all the measured parameters while that of GS1 and MS for a limited number of parameters, probably due to lower quality of MS (lower starch concentration) than required for improved utilization of the GS1-based ration.     

Effect of sex and feeding system on feed intake, growth, and meat and carcass characteristics of fattening Assaf lambs

The effect of feeding system and sex on intake, growth and carcass and meat characteristics of Assaf fattening lambs was studied. Twenty four weaned Assaf lambs, half males and half females were used. After an adaptation period, lambs were randomly assigned to one of the two feeding systems studied. Control lambs received ad libitum commercial concentrate (70% barley, 22% soybean meal, 4.8% wheat, 0.5% bicarbonate, 2.7% mineral–vitamin premix) and barley straw. Free Choice lambs had ad libitum and separate access to whole barley grain and a protein supplement (73.3% soyabean meal, 16% wheat, 1.7% bicarbonate, 9% mineral–vitamin premix). Lambs were slaughtered at 25 kg LBW. Feed intake was not significantly affected by sex (P > 0.05) but Free Choice lambs showed higher dry mater intake than the Control lambs. Nevertheless, only males from the Free Choice group showed an improvement in feed efficiency rate (P < 0.05) and average daily gain (P < 0.01) relating to the Control lambs. Neither feeding system nor feeding system × sex interaction significantly affected non-carcass weight, fat depots, cold carcass weight, dressing percentage, main proportions of commercial cuts and meat characteristics (P < 0.05). As it was expected, female lambs showed a lower average daily gain and a higher feed conversion efficiency than male lambs (P < 0.001) which was related to a greater fat deposition. Meat characteristics were unaffected by sex, with the exception of longissimus lumborum fat content, which was higher in female lambs.The present results suggest that Free Choice feeding system might be suitable for intensively reared male lambs since improvements in daily weight gain and feed conversion rate were achieved, with no adverse effect on carcass and meat quality. Despite the selected diet of both, males and females, did not differ in the crude protein content, the use of Free Choice feeding system for female lambs did not improve performance compared to the Control group.     

Growth and carcass characteristics of male Sahelian goats fed leaves or pods of Pterocarpus lucens or Acacia senegal

The effect of feeding browse on growth and carcass characteristics was studied using thirty-two 10–12 months old growing Sahelian goats weighing an average of 15.6 kg. The treatments were four diets: Acacia senegal pods, Pterocarpus lucens leaves and pods and a positive control. The browses were offered ad libitum and supplemented with 200 g of hay of Schoenefeldia gracilis and 200 g of millet bran, while the control group received 200 g of millet bran, 200 g of cottonseed cake and hay ad libitum. The highest DM intake was observed for goats fed A. senegal pods, resulting in higher CP intake from this diet. The diet with P. lucens leaves gave a higher feed consumption than the control diet, but CP intakes were similar. The goats fed P. lucens pods diet had the lowest CP intake. The higher intake of the A. senegal pods diet resulted in higher growth rate (56 g/day), comparable to the P. lucens leaves and the control diets (55 and 51 g/day respectively). However, the feed conversion ratio was the lowest for the control diet. The carcass weight, dressing percentage and weight of the primal cuts were higher for goats fed A. senegal pods, P. lucens leaves and the control diet. In conclusion A. senegal pods and P. lucens leaves showed good intake characteristics for goats under stall-feeding conditions. Pods from P. lucens, resulting in lower performance, can be fed with small amounts of millet bran for maintenance of goats during the dry season.     

Finishing of dairy steers having grazed semi-natural grasslands

The objective of this study was to determine the effects of initial live weight, level of grain feeding, and length of finishing period on weight gain and carcass traits of dairy steers that had grazed semi-natural grasslands. Steers were subdivided by initial live weight (low vs. high) and were fed two levels of grain (0.5% vs. 1.0% of live weight day^− 1) during three different lengths of finishing period (3, 5 vs. 8 months). In total, 192 steers, initially 18 to 21 months of age, were fed grass–clover silage ad libitum. Steers fed high levels of grain had a higher dietary feed intake than steers fed low levels of grain (10.5 vs. 9.7 kg DM day^− 1; P < 0.001). Carcass weight gain (630 g) was highest and feed conversion (169 MJ metabolizable energy per kg carcass gain) was best in steers with 5 months of finishing. Steers with low initial weights had a higher daily carcass weight gain than initially heavy steers (614 vs. 571 g, P = 0.013). A high initial weight and a long finishing period resulted in heavier and fatter carcasses with a higher conformation score and lower proportions of valuable retail cuts and bone. In conclusion, high-quality carcasses can be produced when finishing dairy steers that previously have grazed semi-natural grasslands. Performance and carcass traits were more effected by initial weight and length of finishing period than by level of grain feeding.     

Intake, performance and carcass characteristics of beef cattle offered diets based on whole-crop wheat or forage maize relative to grass silage or ad libitum concentrates

Seventy beef steers, mean initial live-weight 424 (S.D. 33.0) kg, were blocked by live-weight and breed and allocated to one of 5 dietary treatments in a randomised complete block design. Treatments, including supplementation with 3 kg concentrates/head/day, were grass silage (GS), maize silage (MS), fermented whole-crop wheat (FWCW), urea-treated, processed whole-crop wheat (UPWCW), and ad libitum concentrates supplemented with 5 kg grass silage/head/day (ALC). The grain in urea-treated, processed whole-crop wheat (WCW) was cracked and the crop ensiled with a urea plus urease-based additive. The mean dry matter (DM) of the grass silage, maize silage, fermented WCW and urea-treated, processed WCW was 174, 315, 404 and 716 g/kg, respectively. Total DM intake and carcass growth were lowest for GS (P < 0.001). Relative to ALC, feed conversion efficiency (FCE) (P < 0.05), live-weight gain (P < 0.05), carcass-weight gain (P < 0.01) and kill-out rate (P < 0.05) were lower for GS, FWCW and UPWCW. The MS had a better FCE than the UPWCW (P < 0.001) or the FWCW (P < 0.05). Plasma urea concentration was lowest for MS and highest for UPWCW (P < 0.001). Animals offered the GS treatment had the most yellow fat (higher (P < 0.05) ‘b’ value) and those offered UPWCW had the whitest fat (lower (P < 0.01) ‘b’ value). It is concluded that MS, FWCW and UPWCW supported superior levels of growth by cattle compared to GS (in vitro DM digestibility 674 g/kg). There was no animal productivity advantage with UPWCW compared to FWCW.     

A comparison of finishing systems and duration for spring-born Aberdeen Angus × Holstein-Friesian and Belgian Blue × Holstein-Friesian steers

In Ireland, the majority of dairy cows calve in spring and the male progeny are reared for beef as steers. Over half of all dairy calves are beef crosses with Aberdeen Angus and Belgian Blue representing two extremes in maturity type. The objective of this study was to compare different finishing systems in the autumn/winter of their second year for spring-born steers of contrasting maturity type. A total of 80 spring-born calves, 40 Aberdeen Angus × Holstein-Friesian (AA) and 40 Belgian Blue × Holstein-Friesian (BB) were reared together to 16 months of age. They were then blocked on live weight within breed type and assigned to a pre-experimental slaughter group and to four finishing groups namely: (i) pasture only for 94 days to slaughter, (ii) concentrates ad libitum indoors for 94 days to slaughter, (iii) pasture only for 94 days followed by concentrates ad libitum indoors for 95 days to slaughter, and (iv) concentrates ad libitum indoors for 189 days to slaughter. After slaughter, the 6–10th ribs joint was separated into its component tissues and a sample of m. longissimus was chemically analysed. Mean slaughter weights and carcass weights per day from arrival were 922 and 957 (s.e. 10.6)g, and 476 and 511 (s.e. 6.1) g for AA and BB, respectively. Corresponding carcass weights, kill out proportions, ribs joint fat and muscle proportions, and m. longissimus lipid concentrations were 300 and 322 (s.e. 3.9) kg, 515 and 534 (s.e. 2.4) g/kg, 181 and 121 (s.e. 4.2) g/kg, 605 and 666 (s.e. 4.5) g/kg, and 42 and 25 (s.e. 2.5) g/kg, respectively. Mean daily live weight gains for the finishing treatments as listed were 714, 1539, 999 and 1186 (s.e. 32.0) g, respectively. Corresponding mean daily carcass gains, carcass weights, ribs joint fat proportions and m. longissimus lipid concentrations were 416, 901, 645 and 774 (s.e. 24.6) g, 252, 296, 336 and 359 (s.e. 5.5) kg, 76, 165, 154 and 210 (s.e. 5.9) g/kg, and 13, 34, 32 and 55 (s.e. 3.5) g/kg. It is concluded that BB had heavier carcasses of better conformation with less ribs joint fat and less intramuscular lipid than AA. Neither breed type had acceptably finished carcasses after 94 days on pasture, but both breed types had acceptably finished carcasses following concentrate feeding for 94 days. The carcasses of the BB animals on pasture for 94 days and then finished on concentrates were not acceptably finished and m. longissimus lipid concentration was < 25 g/kg. In contrast, the carcasses of the AA animals finished on concentrates for 189 days were over fat and m. longissimus lipid concentration was > 65 g/kg.     

Effect of parity and progesterone priming on induction of reproductive function in Saanen goats by buck exposure

The response to the buck effect and the use of progesterone priming was studied in Saanen goats during the non-breeding season (April and May) in northern Mexico (26° N). Forty goats were assigned randomly in equal numbers (n = 10) to four treatment groups in a 2 × 2 factorial arrangement. Treatment consisted of two dosages of progesterone (P4) (0 or 5 mg) and two categories of goats, nulliparous and multiparous. Both parity groups were exposed to sexually active bucks previously exposed to a long-day photoperiodic scheme (16 h light day^− 1). All multiparous goats (20/20) displayed estrous behavior within the first 10 days of buck exposure, while 70% (14/20) of the nulliparous goats showed estrus (P > 0.05). During the first five days of buck exposure, the percentage of unprimed goats in estrus was 70% points lower than the primed goats, although progesterone priming did not affect the occurrence of estrus (90% vs 80%; P > 0.05) after 10 days of buck stimulus. The time to onset of estrus was four days shorter (P < 0.05) in P4-treated goats compared with controls. Pregnancy rate did not differ between primed and unprimed goats (80 vs 60%; P > 0.05), but this variable was higher (P < 0.05) in multiparous than nulliparous goats (95 vs 45%). It was concluded that it is possible to induce fertile estrus in Saanen goats during the non-breeding season in northern Mexico using sexually active bucks. The use of progesterone priming can accelerate the response of goats to the buck stimulus although it was ineffective in improving the pregnancy rate of goats. Additionally, a higher proportion of the multiparous goats got pregnant compared with the nulliparous goats induced to estrus by the buck stimulus.     

Carcass characteristics of Awassi ram lambs slaughtered at different weights

Thirty Awassi ram lambs were used to study the effects of slaughter weight on carcass characteristics. Lambs were slaughtered at three different live weights (20, 30, and 40 kg). Empty body weight, hot and cold carcass weights and non-carcass components increased (P < 0.001) at a steady rate between all slaughter weights. Body length, leg length, maximum shoulder width, width behind shoulders and gigot width increased (P < 0.001) as slaughter weight increased from 20 to 40 kg. Linear dimensions measured on the surface of the M. Longissimus also increased (P < 0.001) with increasing slaughter weight. The ratio between width and depth of the longissimus muscle decreased (P < 0.01) at a steady rate between 20 and 40 kg indicating that the muscle increased more in depth than width. Dressing-out percentage was higher (P < 0.001) for lambs slaughtered at 30 kg live weight compared to other weights. Total lean and total bone decreased (P < 0.05) as a percent of cold carcass weight while total fat, subcutaneous and intermuscular fat percentages increased (P < 0.05) with increasing weight. Subcutaneous fat percentage was not affected by increasing body weight between 20 and 30 kg. Intermuscular fat percent was higher in all cuts except the leg where subcutaneous fat % was higher. Muscle to bone ratio increased (P < 0.001) while muscle to fat ratio decreased (P < 0.001) with increasing body weight in the four major cuts and the whole carcass. In conclusion, slaughtering Awassi ram lambs at weights up to 30 kg resulted in higher dressing-out percentage and better carcass characteristics than ram lambs slaughtered at heavier weights.     

Utilization of nutrients as influenced by different restriction levels of feed intake under sub-tropical conditions in crossbred calves

Twenty growing crossbred calves (mean body wt. 159.7 ± 3.94 kg) were randomly divided into 4 groups 5 in each following randomized block design. To assess the voluntary dry matter intake (VDMI) during preliminary feeding period, all the animals were fed concentrate mixture and wheat straw ad libitum. The lowest DMI amongst all animals fed ad libitum was defined as ‘VDMI’. The animals were fed at four fixed levels. The highest level of DMI was 95% of VDMI (group 1) as determined in preliminary period of feeding the other 3 levels were 80% (group 2), 60% (group 3) and 40% (group 4) of the VDMI. The experimental feeding was continued for a month followed by a metabolism trial. The dry matter intake through concentrate (crushed maize 33, deoiled-soya meal 32, wheat bran 32, mineral mixture 2 and common salt 1 part) and roughage (wheat straw) was 40:60. The DMI (kg/d) and percent of body weight ranged from 1.62 (group 4) to 4.06 (group 1) and 1.20 to 2.58, respectively. The CP intake (g/d) varied from 177 to 442 among 4 groups. The intake of DM, OM, CP, EE, NDF, ADF and hemi-cellulose (g/d or g/kg w^0.75) was also significantly (P < 0.05) different among 4 groups. The digestibility of DM in groups 1, 2, 3 and 4 was 59.9, 61.7, 64.6 and 30.4%, respectively and was significantly (P < 0.05) lower in group 4 as compared to the remaining 3 groups. The digestibility of other all nutrients viz. OM, CP, EE, NDF, ADF and HC was comparable among groups 1, 2 and 3. However, the digestibility of these nutrients was significantly (P < 0.05) lower in group 4 (40% intake) as compared to the other 3 groups. Intake and balance of N was significantly (P < 0.01) different among 4 groups, being the lowest in group 4. Animals of groups 1, 2 and 3 were in positive nitrogen balance, however, animals of group 4 were in negative N balance. The results revealed that nutrient utilization was unaffected up to 60% level but it was drastically reduced at 40% level of feed intake. It was also observed that calves maintained on 80 and 60% of feed intake lost body weight (250–300 g/d).     

The effect of dietary barley level on volatile fatty acid concentration and manure ammonia emissions in finishing pigs

An experiment was conducted to investigate the linear and quadratic effects of barley on volatile fatty acid (VFA) profile and manure ammonia emissions in pigs. Sixteen boars (66 kg) were assigned to one of four treatments (n = 4): (T1) 0 g/kg barley (control), (T2) 222 g/kg barley, (T3) 442 g/kg barley and (T4) 666 g/kg barley. Barley was substituted for wheat. The diets were formulated to contain similar concentrations of digestible energy and lysine, soya oil was adjusted to maintain net energy. Increasing barley levels caused a linear decrease in colonic (P < 0.01) and caecal pH (P < 0.001). Total caecal VFA and propionic acid were affected by dietary barley level (quadratic, P < 0.05). There was a linear decrease in the proportion of acetic acid (P < 0.001), isobutyric acid (P < 0.01), isovaleric acid (P < 0.05) with increasing levels of barley in both the caecum and colon. There was a linear increase in the proportion of propionic acid (P < 0.001) and butyric acid (P < 0.05) with increasing barley in the colon. Barley based diets had a lower ammonia emission from 96 to 240 h (P < 0.05) and from 0 to 240 h (P < 0.05) than the wheat based diet. In conclusion, a high level of barley is required to reduce offensive branch chained VFAs.     

Effects of three different concentrate proportions and rapeseed meal supplement to grass silage on animal performance of dairy-breed bulls with TMR feeding

A 3 × 2 factorial design with growing dairy-breed bulls was used to study the effects on animal performance of (1) proportion of concentrate (rolled barley) in the diet, and (2) inclusion of rapeseed meal (RSM) in the barley-based concentrate in a total mixed ration (TMR). The interactions between concentrate proportion and RSM supplement were also examined.Three feeding experiments comprised in total of 84 Finnish Ayrshire bulls and 6 Friesian bulls. The bulls were fed TMR ad libitum. The three concentrate proportions were 300 (L), 500 (M) and 700 (H) g/kg dry matter (DM), fed without RSM (RSM−) or with RSM (RSM+). Rapeseed meal was given so that the crude protein (CP) content of the concentrate was raised to 160 g/kg DM in the RSM+ diets. In the RSM− diets the CP content of the concentrate was 128 g/kg DM, so the CP content increased 25% with RSM supplementation. Increasing the proportion of concentrate led to a linear improvement in daily live weight gain (LWG) (P < 0.05), but there were no significant treatment differences in the DM intake (kg/d). Increasing the proportion of concentrate also led to significantly higher CP (P < 0.001) and phosphorus (P) (P < 0.001) supply and significantly improved DM and organic matter (OM) digestibility (P < 0.001). However, the digestibility of neutral detergent fibre (NDF) decreased (P < 0.001) as the proportion of concentrate increased. The feed conversion rate (kg DM/kg LWG) decreased significantly with increasing concentrate proportion (P < 0.001). Rapeseed meal supplement had no effect on animal performance, but the supply of CP (P < 0.01) and P (P < 0.001) was higher when RSM was included in the diet. The CP (P < 0.001) and NDF (P < 0.05) digestibilities were also higher for the RSM+ diets than for the RSM− diets. Because RSM at the concentration used did not affect animal performance, there is no reason to use RSM supplementation for finishing dairy bulls when there is good quality grass silage and barley-based concentrate in the TMR ration. This study also shows that there is a need to update the Finnish feeding recommendations for dairy-breed growing bulls, and extra calculations are needed for the energy and protein supply of growing dairy bulls.     

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.     

Effects of cinnamaldehyde, garlic and juniper berry essential oils on rumen fermentation, blood metabolites, growth performance, and carcass characteristics of growing lambs

The objective of this study was to examine the effects of cinnamaldehyde (CDH), garlic (GAR) and juniper berry (JUN) essential oils (200 mg/kg of DM) on performance and carcass characteristics of lambs fed a barley-based concentrate diet ad libitum. For this purpose, 40 ewes' lambs (23.5 ± 1.11 kg initial live weight, LW) were used in a random block design over a 13-week period. Feeding CDH, GAR or JUN did not affect dry matter intake (DMI) but the average daily gain (ADG) of lambs supplemented with CDH and JUN was higher (P = 0.002) as compared to lambs fed GAR or the control diet. Feed conversion (DMI/ADG) was numerically improved when lambs were fed CDH (4.8) and JUN (4.7) compared to those fed GAR (5.2) or the control diet (5.3). There were no effects of feed additives on ruminal pH and concentrations of ammonia and total VFA. Serum concentrations of glycerol and total glycerides were lower and higher (P ≤ 0.03) in lambs fed CDH or JUN respectively, as compared to lambs fed GAR or the control diet. Hot dressed carcass weight was similar among treatments (23.7 ± 0.75 kg; P = 0.18) whereas saleable meat tended (P = 0.13) to increase (+ 9%) in lambs fed CDH and JUN compared to those fed GAR or the control diet. Feeding CDH, GAR or JUN had little effect on the overall fatty acid composition of back fat and liver and only minor effects on meat flavour characteristics.     

Effect of castration on productive performance, carcass characteristics and meat quality of Iberian pig females reared under intensive management systems

Sixty crossbred (Iberian dam × Duroc sire) females, 80 days of age (17.6 ± 0.13 kg body weight, BW), was used to investigate the effect of castration on productive performance, carcass and meat quality and fatty acid profile of backfat (BF). There were 2 treatments (intact females, IF; castrated females, CF) and 5 replicates of 6 pigs per treatment. Pigs were reared indoor under an intensive production system, ovariectomized at 92 days of age (26.1 ± 0.19 kg BW) and slaughtered at 267 days of age (143.6 ± 6.49 kg BW). Meat samples were taken at longissimus dorsi muscle at the level of the last rib and BF samples were taken at the tail insertion. For the entire experiment (18 to 144 kg BW), IF ate less feed and were more efficient than CF (P < 0.05). Also, IF had less carcass yield (P < 0.01) and fat thickness at the gluteus medius muscle (P < 0.05) and tended to have lower backfat depth (P < 0.10) than CF. However, IF had higher shoulder yield at 2 and at 24 h post mortem (P < 0.05) and after trimmed (P < 0.10) than CF. The pH₂₄ of the semimembranosus muscle tended to be lower for IF than for CF. Also, IF had more moisture (710 vs. 691 g/kg) and less fat (66.4 vs. 91.2 g/kg) in the longissimus dorsi muscle than CF (P < 0.05). Meat from IF was more lightness (higher L value; P < 0.01), redder (higher a value; P < 0.001) and had more intensive color (higher c value; P < 0.001) than meat from CF. Backfat was more saturated in CF than in IF (P < 0.05), mostly because of the higher palmitic acid (P < 0.05) and the lower linolenic acid (P < 0.05) content. We conclude that intact females have better productive performance and shoulder yield but less carcass yield than castrated females and that castration does not improve meat quality. Therefore, when animal welfare, cost of castration, productive performance and carcass and meat quality traits are considered, the use of intact females rather than castrated females is recommended for the production of Iberian pigs reared under intensive management systems.