A. Aoetpah, C. Gardiner, B. Gummow, A. Mialon, G. Walker
{"title":"不可降解的日粮蛋白质限制了杂交波尔奶牛的生长速度和胴体产量,这些奶牛饲喂的是脱毒草(Desmanthus)干草或添加尿素和/或棉籽粕的罗得草(Chloris gayana)干草","authors":"A. Aoetpah, C. Gardiner, B. Gummow, A. Mialon, G. Walker","doi":"10.1071/an23157","DOIUrl":null,"url":null,"abstract":"<strong> Context</strong><p>Low-protein tropical forages required protein supplementation, which might affect growth of meat goats.</p><strong> Aims</strong><p>This study was aimed to compare liveweight gain, carcass/non-carcass yields and meat quality in crossbred Boer kids fed <i>isonitrogenous</i> diets varying in undegradable (UDP) and rumen-degradable (RDP) dietary protein sources.</p><strong> Methods</strong><p>Twenty-five female crossbred Boer kids were randomly allocated into the following five dietary treatments: Rhodes grass (<i>Chloris gayana</i>) hay supplemented with urea (U), urea plus cottonseed meal (UCSM), cottonseed meal (CSM), gliricidia (<i>Gliricidia sepium</i>) (Gliri) or <i>Desmanthus</i> (<i>Desmanthus leptophyllus</i>) only (Desman). The diets were formulated to supply 135 and 195 g crude protein/kg DM for the two experiments. Experiment 1 lasted 78 days and the dietary UDP:RDP ratio (g/kg DM) was 35:102 (U), 37:100 (UCSM), 40:97 (CSM), 55:82 (Desman) and 46:91 (Gliri). Experiment 2 lasted 138 days and the dietary UDP:RDP ratio (g/kg DM) was 45:150 (U), 52:143 (UCSM), 58:137 (CSM), 83:112 (Desman) and 71:124 (Gliri) respectively. Data were subjected to one-way ANOVA and general linear model.</p><strong> Key results</strong><p>After 138 days of supplementation, the Desman goats had the highest liveweight gain (83 g/day) and heaviest cold carcass weight (12.1 kg) in Experiment 2. This was followed, in descending order, by CSM (58 g/day and 9.6 kg), UCSM (48 g/day and 7.8 kg), Gliri (41 g/day and 7.6 kg) and U (6 g/day and 6.0 kg). Heavier carcass weight was associated with larger eye-muscle area and fat depth at the 12th rib. Aus-meat Beef Colour Standard scores of 3–4 for the eye muscle of the Desman and CSM goats compared with scores of 1C-2 in the other goats meant that the darker meat in Desman and CSM diets was associated with heavier carcass weight and a more rapid rate of decline in carcass pH.</p><strong> Conclusions</strong><p>Crossbred Boer kids fed high dietary UDP had higher intakes of UDP, RDP, metabolisable protein (MP) and metabolisable energy (ME), even though an isonitrogenous diet was offered. The Desman kids had higher liveweight gain, heavier carcass yield, greater eye-muscle area, thicker fat depth and heavier mass of non-carcass components.</p><strong> Implications</strong><p>The higher liveweight gain and carcass/non-carcass yields for Desman goats than for others was associated with increased DM, UDP, RDP, MP and ME intakes.</p>","PeriodicalId":7895,"journal":{"name":"Animal Production Science","volume":"49 1","pages":""},"PeriodicalIF":1.4000,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Undegradable dietary protein limits growth and carcass yields in crossbred Boer kids fed Desmanthus hay or Rhodes grass (Chloris gayana) hay supplemented with urea and/or cottonseed meal\",\"authors\":\"A. Aoetpah, C. Gardiner, B. Gummow, A. Mialon, G. Walker\",\"doi\":\"10.1071/an23157\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<strong> Context</strong><p>Low-protein tropical forages required protein supplementation, which might affect growth of meat goats.</p><strong> Aims</strong><p>This study was aimed to compare liveweight gain, carcass/non-carcass yields and meat quality in crossbred Boer kids fed <i>isonitrogenous</i> diets varying in undegradable (UDP) and rumen-degradable (RDP) dietary protein sources.</p><strong> Methods</strong><p>Twenty-five female crossbred Boer kids were randomly allocated into the following five dietary treatments: Rhodes grass (<i>Chloris gayana</i>) hay supplemented with urea (U), urea plus cottonseed meal (UCSM), cottonseed meal (CSM), gliricidia (<i>Gliricidia sepium</i>) (Gliri) or <i>Desmanthus</i> (<i>Desmanthus leptophyllus</i>) only (Desman). The diets were formulated to supply 135 and 195 g crude protein/kg DM for the two experiments. Experiment 1 lasted 78 days and the dietary UDP:RDP ratio (g/kg DM) was 35:102 (U), 37:100 (UCSM), 40:97 (CSM), 55:82 (Desman) and 46:91 (Gliri). Experiment 2 lasted 138 days and the dietary UDP:RDP ratio (g/kg DM) was 45:150 (U), 52:143 (UCSM), 58:137 (CSM), 83:112 (Desman) and 71:124 (Gliri) respectively. Data were subjected to one-way ANOVA and general linear model.</p><strong> Key results</strong><p>After 138 days of supplementation, the Desman goats had the highest liveweight gain (83 g/day) and heaviest cold carcass weight (12.1 kg) in Experiment 2. This was followed, in descending order, by CSM (58 g/day and 9.6 kg), UCSM (48 g/day and 7.8 kg), Gliri (41 g/day and 7.6 kg) and U (6 g/day and 6.0 kg). Heavier carcass weight was associated with larger eye-muscle area and fat depth at the 12th rib. Aus-meat Beef Colour Standard scores of 3–4 for the eye muscle of the Desman and CSM goats compared with scores of 1C-2 in the other goats meant that the darker meat in Desman and CSM diets was associated with heavier carcass weight and a more rapid rate of decline in carcass pH.</p><strong> Conclusions</strong><p>Crossbred Boer kids fed high dietary UDP had higher intakes of UDP, RDP, metabolisable protein (MP) and metabolisable energy (ME), even though an isonitrogenous diet was offered. The Desman kids had higher liveweight gain, heavier carcass yield, greater eye-muscle area, thicker fat depth and heavier mass of non-carcass components.</p><strong> Implications</strong><p>The higher liveweight gain and carcass/non-carcass yields for Desman goats than for others was associated with increased DM, UDP, RDP, MP and ME intakes.</p>\",\"PeriodicalId\":7895,\"journal\":{\"name\":\"Animal Production Science\",\"volume\":\"49 1\",\"pages\":\"\"},\"PeriodicalIF\":1.4000,\"publicationDate\":\"2024-09-09\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Animal Production Science\",\"FirstCategoryId\":\"97\",\"ListUrlMain\":\"https://doi.org/10.1071/an23157\",\"RegionNum\":4,\"RegionCategory\":\"农林科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"Agricultural and Biological Sciences\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Animal Production Science","FirstCategoryId":"97","ListUrlMain":"https://doi.org/10.1071/an23157","RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"Agricultural and Biological Sciences","Score":null,"Total":0}
Undegradable dietary protein limits growth and carcass yields in crossbred Boer kids fed Desmanthus hay or Rhodes grass (Chloris gayana) hay supplemented with urea and/or cottonseed meal
Context
Low-protein tropical forages required protein supplementation, which might affect growth of meat goats.
Aims
This study was aimed to compare liveweight gain, carcass/non-carcass yields and meat quality in crossbred Boer kids fed isonitrogenous diets varying in undegradable (UDP) and rumen-degradable (RDP) dietary protein sources.
Methods
Twenty-five female crossbred Boer kids were randomly allocated into the following five dietary treatments: Rhodes grass (Chloris gayana) hay supplemented with urea (U), urea plus cottonseed meal (UCSM), cottonseed meal (CSM), gliricidia (Gliricidia sepium) (Gliri) or Desmanthus (Desmanthus leptophyllus) only (Desman). The diets were formulated to supply 135 and 195 g crude protein/kg DM for the two experiments. Experiment 1 lasted 78 days and the dietary UDP:RDP ratio (g/kg DM) was 35:102 (U), 37:100 (UCSM), 40:97 (CSM), 55:82 (Desman) and 46:91 (Gliri). Experiment 2 lasted 138 days and the dietary UDP:RDP ratio (g/kg DM) was 45:150 (U), 52:143 (UCSM), 58:137 (CSM), 83:112 (Desman) and 71:124 (Gliri) respectively. Data were subjected to one-way ANOVA and general linear model.
Key results
After 138 days of supplementation, the Desman goats had the highest liveweight gain (83 g/day) and heaviest cold carcass weight (12.1 kg) in Experiment 2. This was followed, in descending order, by CSM (58 g/day and 9.6 kg), UCSM (48 g/day and 7.8 kg), Gliri (41 g/day and 7.6 kg) and U (6 g/day and 6.0 kg). Heavier carcass weight was associated with larger eye-muscle area and fat depth at the 12th rib. Aus-meat Beef Colour Standard scores of 3–4 for the eye muscle of the Desman and CSM goats compared with scores of 1C-2 in the other goats meant that the darker meat in Desman and CSM diets was associated with heavier carcass weight and a more rapid rate of decline in carcass pH.
Conclusions
Crossbred Boer kids fed high dietary UDP had higher intakes of UDP, RDP, metabolisable protein (MP) and metabolisable energy (ME), even though an isonitrogenous diet was offered. The Desman kids had higher liveweight gain, heavier carcass yield, greater eye-muscle area, thicker fat depth and heavier mass of non-carcass components.
Implications
The higher liveweight gain and carcass/non-carcass yields for Desman goats than for others was associated with increased DM, UDP, RDP, MP and ME intakes.
期刊介绍:
Research papers in Animal Production Science focus on improving livestock and food production, and on the social and economic issues that influence primary producers. The journal (formerly known as Australian Journal of Experimental Agriculture) is predominantly concerned with domesticated animals (beef cattle, dairy cows, sheep, pigs, goats and poultry); however, contributions on horses and wild animals may be published where relevant.
Animal Production Science is published with the endorsement of the Commonwealth Scientific and Industrial Research Organisation (CSIRO) and the Australian Academy of Science.